Prentice hall's federal taxation test bank chapter 14

Prentice hall's federal taxation test bank chapter 14
Prentice hall's federal taxation test bank chapter 14

Prentice Hall's Federal Taxation 2013 Corporations, 26e (Pope)

Chapter C14 Income Taxation of Trusts and Estates

1) For purposes of trust administration, the term "sprinkling" relates to the mandatory distribution of income among various beneficiaries.

Answer: FALSE

Page Ref.: C:14-3

Objective: 1

2) A trust receives no standard deduction when computing taxable income.

Answer: TRUE

Page Ref.: C:14-8

Objective: 3

3) A complex trust permits accumulation of current income, provides for charitable contributions, or distributes principal during the taxable year.

Answer: TRUE

Page Ref.: C:14-9

Objective: 3

4) The distribution deduction for a complex trust is the lesser of the amount distributed or distributable net income, reduced by net tax-exempt income.

Answer: TRUE

Page Ref.: C:14-20

Objective: 6

5) The personal exemption available to a trust is adjusted annually based on changes in the consumer price index.

Answer: FALSE

Page Ref.: C:14-10

Objective: 3

6) Distributable net income (DNI) does not include capital gains allocated to principal.

Answer: TRUE

Page Ref.: C:14-11

Objective: 4

7) The $3,000 limitation on deducting net capital losses does not apply to a trust.

Answer: FALSE

Page Ref.: C:14-16

Objective: 5

8) Distributable net income (DNI) is not reduced by the charitable contribution deduction when calculating the deductible discretionary distributions for a complex trust.

Answer: FALSE

Page Ref.: C:14-20

Objective: 6

9) Income in respect of a decedent (IRD) is included in the decedent's final income tax return. Answer: FALSE

Page Ref.: C:14-27

Objective: 7

10) Income in respect of a decedent (IRD) includes interest earned by a cash-basis taxpayer but not received by the taxpayer before death.

Answer: TRUE

Page Ref.: C:14-28

Objective: 7

11) Grantor trusts are taxed as complex trusts.

Answer: FALSE

Page Ref.: C:14-30

Objective: 8

12) Trusts are required to make estimated tax payments.

Answer: TRUE

Page Ref.: C:14-35

Objective: 10

13) A tax entity, often called a fiduciary, includes all of the following except

A) estates.

B) complex trusts.

C) testamentary trusts.

D) All of the above are fiduciaries.

Answer: D

Page Ref.: C:14-2

Objective: 1

14) Which of the following statements is incorrect?

A) The income tax rules governing estates and trusts are generally identical.

B) Income generated by property owned by an estate or trust is reported on that entity's tax return.

C) Subchapter K contains the special rules applicable to estates and trusts.

D) All of the above are correct.

Answer: C

Explanation: C) Subchapter J contains the rules.

Page Ref.: C:14-2

Objective: 1

15) An inter vivos trust may be created by all of the following except a

A) a grantor.

B) a trustor.

C) an executor.

D) a transferor.

Answer: C

Page Ref.: C:14-2

Objective: 1

16) The executor or administrator is responsible for all the following estate duties except

A) preserving the estate's existence as a separate taxpayer.

B) collecting the assets.

C) paying the debts and taxes.

D) distributing the property.

Answer: A

Page Ref.: C:14-2

Objective: 1

17) Beneficiaries of a trust may receive

A) an income interest only.

B) a remainder interest only.

C) both an income and a remainder interest.

D) Any of the above is correct.

Answer: D

Page Ref.: C:14-3

Objective: 1

18) Revocable trusts means

A) the transferor may not demand the assets be returned.

B) income or estate tax savings for the grantor.

C) the assets in the trust avoid probate.

D) the grantor is always the beneficiary.

Answer: C

Page Ref.: C:14-3

Objective: 1

19) Identify which of the following statements is false.

A) For purposes of trust administration, the term "sprinkling" relates to the discretionary authority of the trustee to distribute income among various beneficiaries.

B) The IRS may terminate an estate as a taxpayer after the expiration of a reasonable period of time for performance of the administrative duties.

C) Assets in a revocable trust do not avoid probate.

D) Assets in a revocable trust are included in the gross estate.

Answer: C

Page Ref.: C:14-3

Objective: 1

20) Which of the following statements regarding the taxation of a trust is incorrect?

A) An irrevocable trust's income is taxed to the grantor.

B) Trusts are generally not taxed at favorable rates for income shifting.

C) Trusts are not subject to double taxation.

D) A trust's long-term capital gains are taxed at a top rate of 15%.

Answer: A

Page Ref.: C:14-4

Objective: 1

21) Identify which of the following statements is false.

A) A conduit approach—that is, the income has the same character in the hands of the beneficiary as it has to the trust—governs for fiduciary income taxation.

B) Essentially, an estate or trust is taxed on any income it earns, whether retained or distributed.

C) Many of the same rules that determine the calculation of taxable income for individuals apply to trusts.

D) Trusts receive a personal exemption.

Answer: B

Page Ref.: C:14-4

Objective: 1

22) The conduit approach for fiduciary income tax means

A) the distributed income has the same character in the hands of the beneficiary as it has to the trust.

B) the distributed income goes to all beneficiaries proportionately.

C) the distributed income is determined by the trustee annually.

D) the distributed income of a remainder interest is determined by the property.

Answer: A

Page Ref.: C:14-4

Objective: 1

23) Texas Trust receives $10,000 interest on U.S. Treasury bonds and $15,000 interest on State of New York bonds. All $25,000 is distributed to the trust beneficiary, Gary. Which of the following statements is correct?

A) Gary has $25,000 of ordinary gross income.

B) Gary has $10,000 of taxable interest income and $15,000 of tax-free interest income.

C) Gary has no taxable income because the trust must pay the tax.

D) Gary has $10,000 of capital gain and $15,000 of tax-free interest income.

Answer: B

Page Ref.: C:14-4; Example C:14-3

Objective: 1

24) The term "trust income" when not preceded by an explanatory word relates most closely to

A) gross income.

B) taxable income.

C) distributable net income.

D) net accounting income.

Answer: D

Page Ref.: C:14-5

Objective: 2

25) A trust has net accounting income of $15,000. In addition, the trust has a $10,000 capital gain, which is not included in net accounting income. The trust is required to distribute the trust income to the beneficiary. The beneficiary will receive

A) $10,000.

B) $15,000.

C) $24,700.

D) $25,000.

Answer: B

Page Ref.: C:14-5; Example C:14-4

Objective: 2

26) If a state has adopted the Revised Uniform Principal and Income Act, which of the following statements is correct?

A) The state law definition of trust income will preempt any other definitions.

B) The definition of trust income in the trust document will preempt all other definitions.

C) Under state law, tax-exempt interest will not be allocated to income.

D) The definition of principal in the trust document must classify capital gains as principal.

Answer: B

Page Ref.: C:14-5 and C:14-6

Objective: 2

27) Identify which of the following statements is false.

A) State trust law preempts the trust document when defining income.

B) The Uniform Act on principal and income requires depreciation to be charged against income.

C) A statement in the trust instrument concerning the allocation of depreciation to principal or income overrides a provision of state law.

D) The Uniform Act allocates royalties to both principal and income.

Answer: A

Page Ref.: C:14-5

Objective: 2

28) Estates and trusts

A) are taxed on state and municipal bond interest.

B) are not taxed on capital gains.

C) receive a deduction for administrative expenses not otherwise deducted on the estate tax return (Form 706).

D) receive a $1,000 personal exemption.

Answer: C

Page Ref.: C:14-8

Objective: 3

29) Identify which of the following statements is false.

A) A trust receives no standard deduction when computing taxable income.

B) Trust tax preparation fees are miscellaneous itemized deductions and subject to the 2% nondeductible floor.

C) There is no limit on a fiduciary's charitable contribution deduction if such a contribution is authorized in the trust instrument.

D) All of the above are false.

Answer: B

Page Ref.: C:14-8

Objective: 3

30) Identify which of the following statements is false.

A) The personal exemption for a trust provides a tax savings when some income is allocated to principal.

B) Distributable net income (DNI) sets the ceiling on the amount of distributions taxed to the beneficiaries.

C) A complex trust must distribute all its income annually.

D) The beneficiaries of a simple trust are taxed on their share of DNI irrespective of the amount they receive.

Answer: C

Page Ref.: C:14-9

Objective: 3

31) Charitable contributions made by a fiduciary

A) are limited to 50% of fiduciary income.

B) must be authorized in the trust instrument in order to be deductible.

C) flows through to be deducted on the beneficiary's tax return.

D) are subject to the 2% floor.

Answer: B

Page Ref.: C:14-8

Objective: 3

32) A trust distributes 30% of its income to Mark and 20% to Nancy. The remaining 50% is accumulated. The trust's depreciation is $1,000. The trust instrument is silent regarding the depreciation deduction. State law requires the depreciation be charged to principal. What part of the depreciation deduction will be allocated to Mark?

A) $0

B) $200

C) $300

D) $1,000

Answer: C

Explanation: C) Mark receives a $300 (0.30 × $1,000) depreciation deduction even though net accounting income is not reduced by depreciation.

Page Ref.: C:14-9; Example C:14-8

Objective: 3

33) A simple trust

A) may make charitable distributions.

B) may make discretionary distributions of principal.

C) may accumulate income.

D) is required to distribute all of its income currently.

Answer: D

Page Ref.: C:14-9

Objective: 3

34) A trust is required to distribute 10% of its income to Eleanor. In addition, the trustee in his discretion may distribute income to Eleanor and/or Marshall. The trust has net accounting income of $50,000, none of which is tax-exempt. The trust distributes the $5,000 mandatory payment to Eleanor and also distributes discretionary amounts of $5,000 to Eleanor and $5,000 to Marshall. How much must Eleanor include in income?

A) $5,000

B) $10,000

C) $50,000

D) none of the above

Answer: B

Page Ref.: C:14-9

Objective: 3

35) Yellow Trust must distribute 33% of its income annually to Patrick. In addition, the trustee in its discretion may distribute additional income to Minna or Patrick. In the current year, the trust has net accounting income and distributable net income of $150,000, none from tax-exempt sources. The trust makes a $50,000 mandatory distribution to Patrick and a discretionary distribution of $20,000 each to Patrick and Minna. What amounts of income do Patrick and Minna report?

Answer: B

Page Ref.: C:14-9

Objective: 3

36) The exemption amount for an estate is

A) $0.

B) $100.

C) $300.

D) $600.

Answer: D

Page Ref.: C:14-10

Objective: 3

37) A trust that is required to distribute all of its income annually receives a personal exemption for the year of

A) $0, because it retains no income.

B) $100.

C) $300.

D) $600.

Answer: C

Page Ref.: C:14-10

Objective: 3

38) A trust is required to distribute all of its income annually. It distributes all of the income and $2,000 of principal to the beneficiary. Which of the following statements is correct?

A) The trust is a complex trust and is allowed a $300 exemption.

B) The trust is a complex trust and is allowed a $100 exemption.

C) The trust is a simple trust and is allowed a $300 exemption.

D) The trust is a simple trust and is allowed a $100 exemption.

Answer: A

Page Ref.: C:14-10

Objective: 4

39) Which of the following is not an addition to trust taxable income when computing distributable net income (DNI)?

A) distribution deduction

B) capital gains allocated to principal

C) tax-exempt interest

D) personal exemption

Answer: B

Page Ref.: C:14-11

Objective: 4

40) A trust has the following results:

The Uniform Act is followed. The trust document requires one-fifth of the income to be distributed annually to David and the remainder of the income to Patty. What is distributable net income?

A) $74,000

B) $72,000

C) $64,000

D) $62,000

Answer: D

Explanation: D) $62,000 net accounting income (which includes the tax-exempt interest), minus $2,000 trustee fee charged to corpus.

Page Ref.: C:14-15

Objective: 5

41) Identify which of the following statements is true.

A) The personal exemption available to a trust is adjusted annually based on changes in the consumer price index.

B) Income received by a trust beneficiary has the same character it had at the trust level.

C) Distributable net income (DNI) excludes tax-exempt income.

D) All of the above are false.

Answer: B

Page Ref.: C:14-15

Objective: 5

42) A simple trust has a distributable net income (DNI) of $50,000 and net accounting income of $60,000, all from taxable sources. The trust has a sole beneficiary, Marty. The trust reports on a calendar tax year and distributes the $60,000 of 2008's net accounting income to Marty on January 20, 2009. No other distributions are made in the current year. Marty's taxable income from the trust this year is

A) $0.

B) $49,700.

C) $50,000.

D) $60,000.

Answer: C

Page Ref.: C:14-16

Objective: 5

43) Identify which of the following statements is true.

A) Beneficiaries of simple trusts are taxed currently on their pro rata share of taxable distributable net income (DNI) regardless of the actual amount distributed to them during the period.

B) The income received by the beneficiaries of the trust loses its character once it is distributed.

C) Capital losses remaining in the final year of a trust do not pass through to the beneficiaries succeeding to the trust property.

D) All of the above are false.

Answer: A

Page Ref.: C:14-16

Objective: 5

44) A trust is required to distribute all of its income currently. Two years ago, it had a $10,000 capital loss. Last year, it had a $3,000 capital gain. This year, the trust is terminated. Albert has a 40% interest in the trust, and Barbara has a 60% interest. Barbara receives a capital loss pass-through of

A) $0.

B) $2,400.

C) $4,200.

D) $7,000.

Answer: C

Explanation: C) 0.60 × $7,000 = $4,200

Page Ref.: C:14-16

Objective: 5

45) In the current year, a trust has distributable net income (DNI) of $30,000. During the year, the trust makes a mandatory distribution to Sarah of $5,000 and a discretionary distribution of $10,000 to Kyle. The trust has no tax-exempt income. The distribution deduction of the trust is

A) $30,000.

B) $15,000.

C) $10,000.

D) $5,000.

Answer: B

Page Ref.: C:14-18

Objective: 5

46) Panther Trust has net accounting income and distributable net income of $100,000, $75,000 from taxable sources and $25,000 from tax-exempt sources. During the year, the trust makes a mandatory distribution to Julius and Steve of $50,000 each. The distribution deduction is

A) $25,000.

B) $50,000.

C) $75,000.

D) $100,000.

Answer: C

Page Ref.: C:14-18

Objective: 5

47) Panther Trust has net accounting income and distributable net income of $100,000, $75,000 from taxable sources and $25,000 from tax-exempt sources. During the year, the trust makes a mandatory distribution to Julius and Steve of $50,000 each. How much of Steve's distribution is taxable?

A) $12,500

B) $25,000

C) $37,500

D) $50,000

Answer: C

Page Ref.: C:14-18

Objective: 5

48) Identify which of the following statements is true.

A) In a complex trust, distributable net income (DNI) does not act as a ceiling on the amount of the distribution deduction.

B) Distributable net income (DNI) is not reduced by the charitable contribution deduction when calculating the deductible discretionary distributions for a complex trust.

C) In a complex trust, distributable net income (DNI) is not reduced by the charitable contribution deduction when comparing DNI with the mandatory distributions in order to determine the amount of the distribution deduction.

D) All of the above are false.

Answer: C

Page Ref.: C:14-20

Objective: 6

49) Identify which of the following statements is true.

A) Tax-exempt income is allocated among beneficiaries in the proportion that total tax-exempt income bears to total distributable net income (DNI).

B) Both income required to be distributed currently and discretionary income distributions are included in tier-1 distributions.

C) Under the tier system, tier-2 beneficiaries are the first to absorb income.

D) All are false.

Answer: A

Page Ref.: C:14-21

Objective: 6

50) Apple Trust reports net accounting income of $40,000, all from taxable sources. The trustee is required to distribute $15,000 annually to Megan. The trustee also makes discretionary distributions of $30,000, $7,500 to Megan and $22,500 to Caroline. The trust pays $5,000 of the discretionary distributions from corpus. What is the taxable amount of the Megan's tier-2 distribution?

A) $7,500

B) $6,250

C) $15,000

D) $22,500

Answer: B

Explanation: B) 40,000 - 15,000 tier-1 distribution = $25,000. (7,500/30,000) × 25,000 = 6,250.

Page Ref.: C:14-22

Objective: 6

51) Identify which of the following statements is true.

A) An individual cannot be both a tier-1 and tier-2 beneficiary in the same year.

B) Tier-2 beneficiaries potentially can receive more favorable tax treatment than tier-1 beneficiaries.

C) Bequests of specific sums of money when distributed out of an estate result in the recognition of gross income by the beneficiary receiving the bequest.

D) All of the above are false.

Answer: B

Page Ref.: C:14-22

Objective: 6

52) A trust has net accounting income of $30,000, but distributable net income (DNI) of only $25,000 because certain expenses are charged to principal. The trust is required to distribute $10,000 to Alice and it makes a discretionary distribution of $20,000 to Ben. The trust has no tax-exempt income. The amount that Ben reports as gross income is

A) $20,000.

B) $16,667.

C) $15,000.

D) none of the above

Answer: C

Explanation: C) $25,000 DNI (the smaller of the net accounting income or DNI numbers) - $10,000 mandatory distribution to Alice = $15,000

Page Ref.: C:14-22

Objective: 6

53) A trust has net accounting income and distributable net income (DNI) of $60,000, all from taxable sources. The trustee is required to distribute $40,000 of current income to Harry. In addition, the trustee makes a discretionary distribution to Harry of $10,000 and a discretionary distribution to Susan of $30,000. $20,000 of the $40,000 total discretionary distributions is from corpus. Gross income reportable by Harry is

A) $50,000.

B) $45,000.

C) $37,500.

D) $30,000.

Answer: B

Explanation: B) $20,000 × ($10,000/$40,000) = $5,000 discretionary distribution + $40,000 mandatory distribution = $45,000

Objective: 6

54) Martha died and by her will, specifically bequeathed, and the executor distributed, $20,000 cash and a $70,000 house to Harold. The distributions were made in a year in which the estate had $65,000 of DNI, all from taxable sources. The maximum Harold will be required to report as gross income as a result of these distributions is

A) $0.

B) $20,000.

C) $65,000.

D) $70,000.

Answer: A

Page Ref.: C:14-23

Objective: 6

55) An estate made a distribution to its sole beneficiary of $15,000 for the year. This distribution was not the result of a specific bequest. The estate had $40,000 of taxable interest and $34,000 of expenses attributable to earning that interest. What amount of the distribution is taxable to the beneficiary?

A) $40,000

B) $15,000

C) $6,000

D) $0

Answer: C

Page Ref.: C:14-23

Objective: 6

56) Fred, a cash-basis taxpayer, died on January 15, 2007. In 2008, the estate made a $9,000 distribution from estate income to Fred's sole heir. The estate had $20,000 of taxable interest and a $10,000 net long-term capital gain allocable to corpus. The estate incurred $5,000 in expenses attributable to the estate income. What is the estate's distributable net income (DNI)?

A) $15,000

B) $20,000

C) $25,000

D) $30,000

Answer: A

Page Ref.: C:14-23

Objective: 6

57) Apple Trust reports net accounting income of $40,000, all from taxable sources. The trustee is required to distribute $15,000 annually to Megan. The trustee also makes discretionary distributions of $30,000, $7,500 to Megan and $22,500 to Caroline. The trust pays $5,000 of the discretionary distributions from corpus. What is the amount of the distribution deduction?

A) $40,000

B) $45,000

C) $15,000

D) $30,000

Answer: A

Page Ref.: C:14-25

Objective: 6

58) An example of income in respect to a decedent (IRD) for a cash method of accounting taxpayer is

A) interest earned but not received prior to death.

B) salary earned but not received prior to death.

C) gain from an installment sale entered into before death.

D) All of the above are examples.

Answer: D

Page Ref.: C:14-27 and C:14-28

Objective: 7

59) Joyce passed away on January 3 while on an extended holiday cruise celebrating a very successful, and most profitable previous year. Joyce was the chief executive officer of the Quillip Corporation. After the independent audit of Quillip's last year's financial statements was completed in February of this year, Joyce's estate received a $1,000,000 bonus check resulting from last year's corporate profits. Joyce's estate also sold Quillip stock for $500,000 in February of this year. Joyce originally purchased this stock eight years ago for $10,000. The stock was valued at $495,000 on her date of death. Solely based on the above facts, how much income in respect of a decedent should Joyce's estate report in the current year?

A) $1,485,000

B) $1,000,000

C) $485,000

D) $5,000

Answer: B

Page Ref.: C:14-27 and C:14-28

Objective: 7

60) Identify which of the following statements is true.

A) Income in respect of a decedent (IRD) is the gross income the decedent earned before death but had not collected before death.

B) An estate may deduct up to $5,000 of capital losses against the ordinary income taxable in the estate.

C) An example of income in respect of a decedent (IRD) is the gain recognized on property sold by the estate after the decedent's death.

D) All of the above are false.

Answer: A

Page Ref.: C:14-27

Objective: 7

61) Identify which of the following statements is false.

A) Federal estate taxes related to income in respect of a decedent (IRD) is deductible by the estate in the year the IRD is includible in the estate's gross income.

B) An example of deductions in respect of a decedent (DRD) are property taxes that accrued prior to the decedent's death but were not paid until after death.

C) Items of IRD receive a step-up in basis as a result of the decedent's death.

D) Interest earned but not received before death is IRD.

Answer: C

Page Ref.: C:14-27 and C:14-28

Objective: 7

62) Michael died in 2011 with a taxable estate and estate tax base of $6,000,000. Michael's estate owed no state death taxes. Michael's estate includes $250,000 of income in respect of a decedent (IRD), none of which is received by his surviving spouse. His estate had no DRD. The estate collects $200,000 of the IRD during its current tax year. The Sec. 691(c) deduction for the estate in current year is

A) $153,000.

B) $122,400.

C) $112,500.

D) $90,000.

Answer: D

Tax on IRD collected 112,500 × (200,000/250,000) = $87,500.

Page Ref.: C:14-29; Example C:14-31

Objective: 7

63) Identify which of the following statements is true.

A) Under the grantor trust rules, a grantor may be taxed on all or a portion of the trust's income even though the income is distributed to the named beneficiary or someone else.

B) An irrevocable trust cannot be a grantor trust.

C) Large amounts of income can be shifted to children under the age of 18 through the use of trusts that make distributions, and the income will be taxed at the lower rates of the children.

D) All of the above are false.

Answer: A

Page Ref.: C:14-30

Objective: 8

64) Sally transfers property to a revocable trust. Under the terms of the trust agreement, Allison is to receive income for ten years at which time the remainder is to go to Tom. During the year, the trust earns $10,000 in corporate bond interest income and recognizes a capital gain of $20,000. The interest is distributed to Allison and the capital gain is properly allocated to principal. Allison (not Sally) will pay tax on

A) $0.

B) $10,000.

C) $20,000.

D) $30,000.

Answer: A

Explanation: A) The revocable trust is a grantor trust.

Page Ref.: C:14-31; Example C:14-33

Objective: 8

65) Five years ago, Jon transferred stock to an irrevocable trust with First Bank named as trustee, and provided that the trustee is to pay some or all of the trust income to the beneficiary Dan for 15 years. At the end of the 15th year, the trust property, including any undistributed income, will revert to Jon. In the current year, the trust collected $52,000 of dividend income, and distributed $30,000 of this amount to Dan. In addition, the trust sold some of the stock at a $6,000 capital gain. For the current year, the tax results occurred?

A) Dan is taxed on $30,000 of dividends and the trust on the remaining dividends, plus the capital gain, less the $100 personal exemption.

B) The trust is taxed on the $52,000 of dividends less the $100 personal exemption, and Jon is taxed on the capital gain.

C) Dan is taxed on $30,000 of dividends, and the remaining dividends plus the capital gain are taxed to Jon.

D) Jon is taxed on all of the dividends and on the capital gain.

Answer: D

Page Ref.: C:14-30 and C:14-31

Objective: 8

66) In which of the following situations will the grantor trust rules apply?

A) The trust is revocable and mandates the distribution of income to the named beneficiary.

B) The trust is irrevocable, and the trustee, who is also the grantor, has the power to distribute or accumulate income for the named beneficiary.

C) The trust is irrevocable, the income must be paid out currently, and the trust assets will revert to the grantor at the end of nine years.

D) The grantor trust rules will apply in each of the situations.

Answer: D

Page Ref.: C:14-30 through C:14-33

Objective: 8

67) Karly created a $300,000 trust that provided her mother with a lifetime income interest starting on January 1, with the remainder to go to her son. Karly expressly retained the power to revoke both the income and remainder interests at any time. Who will be taxed on the trust's income?

A) Karly's mother

B) Karly's son

C) Karly

D) the trust

Answer: C

Page Ref.: C:14-31

Objective: 8

68) Which of the following is the most accurate statement concerning the use of trusts in tax planning?

A) The grantor trust rules allow grantors to shift income into trusts and reduce their own taxes.

B) Nontax reasons for the use of trusts (such as avoidance of probate) typically outweigh tax reasons for creating trusts today.

C) The large 15% tax bracket available to trusts allows complex trusts to be used as an income-shifting device.

D) None of the above statements are correct.

Answer: B

Page Ref.: C:14-30

Objective: 8

69) All of the following are advantages of a sprinkling trust, except

A) the trustee can choose the amount to distribute among multiple beneficiaries.

B) the trustee can determine the amount to retain in the trust.

C) the trustee can determine the amount to distribute to the sole trust beneficiary.

D) the trustee can consider the tax rates of the beneficiaries and trust.

Answer: C

Page Ref.: C:14-34

Objective: 8

70) Marge died on August 24 of the current year. Her estate collected taxable bond interest of $10,000 per month beginning in September. The only beneficiary of Marge's estate is Art, a calendar-year taxpayer. Which of the following statements is correct?

A) If the estate selects November 30 as a year-end and makes no distributions prior to that date, the estate will be taxed on $30,000 less a $600 personal exemption for its first tax year.

B) If the estate selects January 31 of next year at its year-end and distributes $40,000 to Art in December of this year and nothing in January, the $40,000 will be taxed on Art's next year's tax return.

C) If the estate selects December 31 as its year-end and distributes nothing to Art in December and $40,000 in January of next year, $40,000 less the $600 personal exemption will be taxed on the estate's first tax return.

D) All of the above are correct.

Answer: D

Page Ref.: C:14-35

Objective: 9

71) Mary died this year. Her will creates a trust for the benefit of her children. A portion of the estate's assets are placed in this trust. The estate has income from assets it will transfer to other beneficiaries at a later date. Mary's brother Joe is the trustee of the trust and executor of the estate. Which of the following statements is true?

A) Joe must choose December 31 as the tax year-end for both the estate and trust.

B) Joe is free to choose any tax year-end for both the trust and estate.

C) Joe must choose December 31 as the estate tax year-end but is free to choose any tax year-end for the trust.

D) Joe must choose December 31 as the trust tax year-end but is free to choose any tax year-end for the estate.

Answer: D

Page Ref.: C:14-34

Objective: 10

72) Administration expenses incurred by an estate

A) are deductions in respect of a decedent and may be deducted on both the estate tax return (Form 706) and the estate income tax return (Form 1041).

B) an executor must elect where to deduct administration expenses (Form 706 or Form 1041).

C) such expenses are only deductible on Form 706.

D) such expenses are only deductible on Form 1041.

Answer: B

Page Ref.: C:14-35

Objective: 9

73) Identify which of the following statements is true.

A) All trusts and estates must use a calendar year-end.

B) All estates with gross income of at least $500 must file an income tax return.

C) Trusts are required to make estimated tax payments.

D) All of the above are false.

Answer: C

Page Ref.: C:14-35

Objective: 10

74) Briefly discuss the reasons for establishing a trust.

Answer: Possible tax savings, professional management of assets, restrictions on the donee's use or consumption of assets, protect assets from creditors.

Page Ref.: C:14-3

Objective: 1

75) Briefly discuss some of the reasons for using a revocable trust.

Answer: The grantor may wish to have his property managed by an individual or institution with superior management skills.

The grantor may wish to avoid high probate costs. The grantor may wish to avoid the publicity of probate.

Page Ref.: C:14-3

Objective: 1

76) This year, the Huang Trust received $20,000 of dividends and $30,000 of tax-free interest. It distributes all of its receipts to its beneficiary. How should the beneficiary treat the distribution?

Answer: The beneficiary is deemed to receive $20,000 of taxable dividend income and $30,000 of tax-free interest.

Page Ref.: C:14-4; Example C:14-3

Objective: 1

77) The governing instrument for the Lopez Trust contains no definitions of income and principal. The Trust is located in a state that has adopted the Uniform Act. In the current year, the trust reports the following receipts and disbursements:

Dividends $10,000

Proceeds from sales of stock, including $10,000 of gain $40,000

Trustee's fee, all charged to income $ 500

CPA's fee for preparation of tax return $ 200

What is the trust's net accounting income?

Answer: $10,000 - $500 - $200 = $9,300. The gain on the sale of stock and the rest of the sales proceeds constitute corpus.

Page Ref.: C:14-6; Example C:14-5

Objective: 2

78) A trust document does not define income and principal. The state in which the trust is operated has adopted the Uniform Act. The trust reports the following:

Dividends $2,500

Capital gain 1,500

Tax return preparation fee 200

Trustee fees, all charged to income 100

What is the amount of trust's net accounting income?

Answer: $2,500 - ($200 + $100) = $2,200

Page Ref.: C:14-6; Example C:14-5

Objective: 2

79) Little Trust, whose trust instrument is silent with respect to depreciation, collects rental income of $20,000 and pays property taxes of $1,000. Depreciation expense is $5,000.

Little Trust is in a state where all depreciation is charged to principal. What is the trust's net accounting income?

Answer: $20,000 - $1,000 = $19,000

Page Ref.: C:14-6; Example C:14-6

Objective: 2

80) A trust document does not define income or principal. The state in which the trust is operated has adopted the Uniform Act, including allocation of depreciation to income. The trust reports the following: Net business profits $20,000

Net rental income 5,000

Proceeds from stock sale

(including $10,000 gain) 50,000

Trustee fee (charged to income) 2,000

Depreciation 3,000

What is the amount of the trust's net accounting income?

Answer: $20,000 + $5,000 - $2,000 - $3,000 = $20,000

Page Ref.: C:14-6; Example C:14-6

Objective: 2

81) A trust document does not mention the treatment for depreciation. The state has adopted the Uniform Act. The trust results are the following:

Business net profits $2,000

Rental income 1,000

Depreciation 100

Rent expense 100

Calculate net accounting income.

Answer: $2,000 + $1,000 - $100 - $100 = $2,800. Under the Uniform Act, depreciation is charged to income and therefore reduces net accounting income.

Page Ref.: C:14-6

Objective: 2

82) Ebony Trust was established two years ago with Brent as the beneficiary. The trust instrument instructed the trustee last year to make discretionary distributions of income to Brent. Beginning in two years, the trustee is instructed to pay all of the trust income earned that year to Brent. What was the

trust's personal exemption last year? What will the personal exemption be in two years?

Answer: Last year, the exemption was $100 since the trust did not have to distribute all of its income. Two years from now the personal exemption will be $300 since it will be required to distribute all of its income.

Page Ref.: C:14-10; Example C:14-10

Objective: 3

83) A trust must distribute all of its income annually. Capital gains are allocated to principal. The trust has dividend income of $12,000, capital gains of $6,000, and no expenses. Calculate the trust's taxable income.

Answer: $6,000 - $300 = $5,700

Page Ref.: C:14-10; Example C:14-11

Objective: 3

84) Melody Trust has $60,000 of DNI for the current year, $20,000 of rental income and $40,000 of corporate bond interest. The trust instrument requires the trustee to distribute 30% of the trust income to Lee and 70% to Sarah, annually. The trust instrument does not require an allocation of the different types of income to the two beneficiaries. What is the amount and composition of the income reported by Lee and Sarah, respectively?

Answer: Lee reports $18,000 (30% of $60,000) of trust income and Sarah reports $42,000 (70% of $60,000). Because rents make up one-third ($20,000/$60,000) of DNI, the composition of the income reported by Lee and Sarah is one-third rental income and two-thirds corporate bond interest.

Page Ref.: C:14-11; Example C:14-12

Objective: 4

霍尔电流传感器的应用场合

霍尔电流传感器的应用场合 1、继电保护与测量:在工业应用中,来自高压三相输电线路电流互感器的二次电流,如分别经三只霍尔电流传感器,按比例转换成毫伏电压输出,然后再经运算放大器放大及有源滤波,得到符合要求的电压信号,可送微机进行测量或处理。在这里使用霍尔电流传感器可以很方便地实现了无畸变、无延时的信号转换。 2、在直流自动控制调速系统中的应用:在直流自动控制调速系统中,用霍尔电流电压传感器可以直接代替电流互感器,不仅动态响应好,还可实现对转子电流的最佳控制以及对晶闸管进行过载保护。 3、在逆变器中的应用:在逆变器中,用霍尔电流传感器可进行接地故障检测、直接侧和交流侧的模拟量传感,以保证逆变器能安全工作。 4、在不间断电源中的应用:在该应用中,用霍尔电流传感器进行控制,保证逆变电源正常工作。使用霍尔电流传感器1发出信号并进行反馈,以控制晶闸管的触发角,霍尔电流传感器2发出的信号控制逆变器,霍尔电流传感器3控制浮充电源。由于其响应速度快,霍尔电流传感器特别适用于计算机中的不间断电源。 5、在电子点焊机中的应用:在电子点焊机电源中,霍尔电流传感器起测量和控制作用。它的快速响应能再现电流、电压波形,将它们反馈到可控整流器A、B,可控制其输出。用斩波器给直流迭加上一个交流,可更精确地控制电流。用霍尔电流传感器进行电流检测,既可测量电流的真正瞬时值,又不致引入损耗。 6、用于电车斩波器的控制:电车中的调速是由调整电压实现的。而将霍尔电流传感器和其它元件配合使用,并将传感器的所有信号输入控制系统,可确保电车正常工作。 7、在交流变频调速电机中的应用:用变频器来对交流电机实施调速,在世界各发达国家已普遍使用,且有取代直流调速的趋势。用变频器控制电机实现调速,可节省10%以上的电能。在变频器中,霍尔电流传感器的主要作用是保护昂贵的大功率晶体管。由于霍尔电流传感器的响应时间往往小于5μs,因此,出现过载短路时,在晶全管未达到极限温度之前即可切断电源,使晶体管得到可靠的保护。 8、用于电能管理:霍尔电流传感器,可安装到配电线路上进行负载管理。霍尔电流传感器的输出和计算机连接起来,对用电情况进行监控,若发现过载,便及时使受控的线路断开,保证用电设备的安全。用这种装置,也可进行负载分配及电网的遥控、遥测和巡检等。

密度表观密度体积密度和堆积密度

密度、表观密度、体积密度和堆积密度 密度是指材料在绝对密实状态下单位体积的质量。表观密度是材料在包括闭口孔隙条件下单位体积的质量。体积密度是指材料在自然状态下的体积,包括材料实体及其开口与闭口孔隙条件下的单位体积的质量。堆积密度是指散粒或纤维状材料在堆积状态下单位体积的质量。密度、表观密度、体积密度和堆积密度既有联系又有差别。 材料的孔隙率是指材料内部孔隙的体积占材料总体积的百分率。空隙率则是指散粒状材料在堆积体积状态下颗粒固体物质间空隙体积(开口孔隙与间隙之和)占堆积体积的百分率。材料的孔隙有闭口和开口,其特征状态对材料的性质有重要影响。 材料内部孔隙示意 密度 密度是指材料在绝对密实状态下单位体积的质量。按下式计算: 式中ρ——材料的密度,g/cm3; m——材料的质量(干燥至恒重),g; V——材料在绝对密实状态下的体积,cm3。 除了钢材,玻璃等少数材料外,绝大多数材料内部都有一些孔隙。在测定有孔隙材料(如砖、石等)的密度时,应把材料磨成细粉,干燥后,用李氏瓶测定其绝对密实体积。材料磨得越细,测得的密实体积数值就越精确。 另外,工程上还经常用到比重的概念,比重又称相对密度,是用材料的质量与同体积水(4℃)的质量的比值表示,无单位,其值与材料密度相同(g/cm3)。 表观密度 表观密度是指单位体积(含材料实体及闭口孔隙体积)物质颗粒的干质量,也称

视密度。按下式计算: 式中ρ′——材料的表观密度,kg/m3或g/cm3; m——材料的质量,kg或g; V′——材料在包含闭口孔隙条件下的体积(即只含内部闭口孔,不含开口孔),见图1-2,m3或cm3。 通常,材料在包含闭口孔隙条件下的体积式采用排液置换法或水中称重法测量。 体积密度 体积密度是指材料在自然状态下单位体积(包括材料实体及其开口孔隙、闭口孔隙)的质量,俗称容重。体积密度可按下式计算: 式中ρ0——材料的体积密度,kg/m3或g/cm3; m——材料的质量,kg或g; V0——材料在自然状态下的体积,包括材料实体及其开口孔隙、闭口孔隙,见图1-1,m3或cm3。 对于规则形状材料的体积,可用量具测得。如加气混凝土砌块的体积是逐块量取长、宽、高三个方向的轴线尺寸,计算其体积。对于不规则形状材料的体积,可

材料的密度、表观密度与堆积密度

表示材料物理状态特征的性质 1、体积密度:材料在自然状态下单位体积的质量称为体积密度。 2、密度:材料在绝对密实状态下单位体积的质量称为密度。 3、堆积密度:散粒材料在规定装填条件下单位体积的质量称为堆积密度。 注意:密实状态下的体积是指构成材料的固体物质本身的体积;自然状态下的体积是指固体物质的体积与全部孔隙体积之和;堆积体积是指自然状态下的体积与颗粒之间的空隙之和。 4、表观密度:材料的质量与表观体积之比。表观体积是实体积加闭口孔隙体积,此体积即材料排开水的体积。 5、孔隙率:材料中孔隙体积与材料在自然状态下的体积之比的百分率。 6、开口孔隙率:材料中能被水饱和(即被水所充满)的孔隙体积与材料在自然状态下的体积之比的百分率。 7、闭口孔隙率:材料中闭口孔隙的体积与材料在自然状态下的体积之比的百分率。即闭口孔隙率=孔隙率-开口孔隙率。 8、空隙率:散粒材料在自然堆积状态下,其中的空隙体积与散粒材料在自然状态下的体积之比的百分率。 什么是绝对密实状态 悬赏分:20 - 提问时间2009-8-25 20:25问题为何被关闭 建筑材料课程中有“绝对密实状态”一词,绝对密实状态是什么意思啊? 说的细一点哦! 提问者:秦瀛 - 四级答复共 1 条 理想状态,无孔隙的。玻璃一类的可以理想地看做绝对密实。 绝对密实状态下的体积是指不包括孔隙在内的体积,材料在自然状态下的体积减去材料内部孔隙的体积。 测量密度时,由于一般材料的内部均含有一些孔隙,为了获得绝对密实状态的试样,须将材料磨成细粉以排除其内部孔隙,再用排液置换法求出材料的绝对密实体积。 材料的密实度是指材料在绝对密实状态下的体积与在自然状态下的体积之比。凡是内部有孔隙的材料,其密实度都小于1.材料的密实度反映固体材料中固体物质的充实程度,密实度的大小与其强度、耐水性和导热性等很多性质有关。 材料的密度、表观密度与堆积密度 材料的密度、表观密度与堆积密度 1、密度:密度是材料在绝对密实状态下,单位体积的质量。——密度自身体积 (不含孔隙)磨成细粉消除内部孔隙,材料的排水体积 V 计算式ρ= m/v 式中ρ--- 材料的密度,g/㎝3 。 m --- 材料在干燥状态下的质量,g 。 v --- 材料在绝对密实状态下的体积,㎝3。

霍尔传感器用法

一、霍尔电流电压传感器、变送器的基本原理与使用方法 1.霍尔器件 霍尔器件是一种采用半导体材料制成的磁电转换器件。如果在输入端通入控 制电流I C ,当有一磁场B穿过该器件感磁面,则在输出端出现霍尔电势V H 。 如图1-1所示。 霍尔电势V H 的大小与控制电流I C 和磁通密度B的乘积成正比,即:V H =K H I C Bsin Θ 霍尔电流传感器是按照安培定律原理做成,即在载流导体周围产生一正比于该电流的磁场,而霍尔器件则用来测量这一磁场。因此,使电流的非接触测量成为可能。 通过测量霍尔电势的大小间接测量载流导体电流的大小。因此,电流传感器经过了电-磁-电的绝缘隔离转换。 2.霍尔直流检测原理 如图1-2所示。由于磁路与霍尔器件的输出具有良好的线性关系,因此霍尔 器件输出的电压讯号U 0可以间接反映出被测电流I 1 的大小,即:I 1 ∝B 1 ∝U 我们把U 0定标为当被测电流I 1 为额定值时,U 等于50mV或100mV。这就制成 霍尔直接检测(无放大)电流传感器。

3.霍尔磁补偿原理 原边主回路有一被测电流I1,将产生磁通Φ1,被副边补偿线圈通过的电流I2所产生的磁通Φ2进行补偿后保持磁平衡状态,霍尔器件则始终处于检测零磁通的作用。所以称为霍尔磁补偿电流传感器。这种先进的原理模式优于直检原理模式,突出的优点是响应时间快和测量精度高,特别适用于弱小电流的检测。霍尔磁补偿原理如图1-3所示。 从图1-3知道:Φ 1=Φ 2 I 1N 1 =I 2 N 2 I 2=N I /N 2 ·I 1 当补偿电流I 2流过测量电阻R M 时,在R M 两端转换成电压。做为传感器测量电 压U 0即:U =I 2 R M 按照霍尔磁补偿原理制成了额定输入从0.01A~500A系列规格的电流传感器。 由于磁补偿式电流传感器必须在磁环上绕成千上万匝的补偿线圈,因而成本增加;其次,工作电流消耗也相应增加;但它却具有直检式不可比拟的较高精度和快速响应等优点。 4.磁补偿式电压传感器 为了测量mA级的小电流,根据Φ 1=I 1 N 1 ,增加N 1 的匝数,同样可以获得高磁 通Φ 1 。采用这种方法制成的小电流传感器不但可以测mA级电流,而且可以测电压。 与电流传感器所不同的是在测量电压时,电压传感器的原边多匝绕组通过串 联一个限流电阻R 1,然后并联连接在被测电压U 1 上,得到与被测电压U 1 成比 例的电流I 1 ,如图1-4所示。

霍尔电流传感器及其应用

霍尔电流传感器及其应用 在现代社会中,信息化的需求越来越庞大,传感器在信息采集中发挥了重要作用。他们可以把各种物理信息,按照一定的规则,为可测量的电信号。我们所测量的电信号,以及相关物理信息的关系的变化的基础上,我们可以得到所测量的物理的变化或大小。 根据该传感器的工作原理,我们可以划分成多种类型的传感器,如光电传感器,电荷传感器,电位型传感器,半导体传感器,电传感器,磁传感器,谐振式传感器,电动化学式传感器等等。 霍尔传感器是利用霍尔元件的霍尔效应原理,(可以音乐会的物理信息),如电流,磁场,位移,压力等,为电动势输出。它属于电位型传感器。当前,这种传感器主要是霍尔集成电路,核心单元是基于霍尔效应。这是由通过集成电路技术。因此,它不仅仅是一种集成电路,而是一种磁传感器。 本文根据实际应用,主要是霍尔电流传感器。 1 霍尔效应 在金属或半导体晶片放置在磁场中,并且如果有一个通过它的电流,会产生电动势,(在垂直方向上的电场和磁场,调用此种物理现象霍尔效应。) 在磁场中产生的洛伦兹力的作用下,通电的半导体芯片的载体,分别偏移积累到芯片的两侧,从而形成一个电场,称霍尔电场。霍尔电场产生的电场力,是相反的洛伦兹力,阻碍了继续堆积,直到(大厅)电场力和洛伦兹力。此时,芯片的两侧,将设置一个稳定的电压,这是霍尔电压。 2 霍尔电流传感器 随着城市人口和城市建设规模的扩大,以及各种电气设备的增加,功耗也越来越大。城市的供电设备经常超载,而电源环境越来越差,“测试”的权利越来越严重。因此电源问题越来越多的显现出来。现在,小功率电源设备已经越来越多的与新技术相结合。例如,开关电源,硬切换,软切换,参数稳压器,线性反馈稳压器,磁放大器技术,数控压力调节,PWM,,SPWM,电磁兼容等实际需求直接推动电源技术的发展和进步。为了检验并显示当前自动,自动保护功能和更先进的智能控制,过电流,过电压的危害。如发生时,电源技术与传感检测,传感采样,传感保护已成为一种趋势。传感器检测电流或电压,所谓的霍尔电流传感器应运而生,(并迅速成为最喜爱的设计师在我国的电源). 2.1 霍尔电流传感器的性能特性 霍尔电流传感器具有优越的性能,并且它是一种先进的电检测元件,它可以隔离主回路和电子控制电路。它有变压器和分流器的所有优点,并且在同一时间,克服了他们的缺点(变压器可以只施加的电源频率的测量,50赫兹,分流器是无法做隔离测量),使用同一个霍尔电流传感器模块检测元素,不仅可以测量AC,也可以检测直流,甚至可以检测瞬时峰值。它具有以下性能特点。 (1)测量任意波形的电流,如DC,AC乃至瞬态峰值参数测量的; (2)精度高。在工作区中的一般霍尔电流传感器模块的精度高于1%,并且是适用于任何波形测量精度; (3)线性度优于0.5%; (4)良好的动态性能。一般的电流传感器模块的动态响应时间小于7us,跟踪速度di|dt 是上述50A|us; (5)工作频段宽。它可以工作在频率范围从0到20KHZ非常好; (6)过载能力强。测量范围宽(0-10000A); (7)高可靠性。平均无故障工作是超过5*10000小时; (8)体积小,重量轻,易于安装系统,不会带来任何损失。

表观密度与堆积密度

密度、表观密度与堆积密度 (1) 密度 密度是指材料在绝对密实状态下单位体积的质量。按下式计算: 式中ρ——密度,g/cm3; m——材料的质量,g; V——材料在绝对密实状态下的体积,cm3。 绝对密实状态下的体积是指不包括孔隙在内的体积。所以材料的密度大小取决于材料的组成与材料的微观结构,当材料的组成与结构一定时,材料的密度为常数。除了钢材、玻璃等少数材料外,绝大多数材料都有一些孔隙。在测定有孔隙材料的密度时,应把材料磨成细粉,干燥后,用李氏瓶测定其实体积。材料磨得越细,测得的密度数值就越精确。砖、石材等块状材料的密度即用此法测得。 (2) 表观密度 表观密度是指材料在自然状态下单位体积的质量,按下式计算: 式中ρo——表观密度,g/cm3或kg/cm3; m——材料的质量,g或kg; V o——材料在自然状态下的体积,或称表观体积,cm3或m3。 材料的表观体积是指材料及所含内部孔隙的总体积,材料在自然状态下的质量与其含水状态关系密切,且与材料孔隙的具体构造特征

有关。故测定表观密度时,必须注明其含水情况,一般是指材料在气干状态(长期在空气中干燥)下的表观密度。在烘干状态下的表观密度,称为干表观密度。不含开口孔隙的表观密度称为视密度,以排水法测定其体积。 (3) 堆积密度 堆积密度是指粉状或粒状材料在堆积状态下单位体积的质量,按下式计算: 式中——堆积密度,kg/m3; m——材料的质量,kg; ——材料的堆积体积,m3。 测定散粒材料的堆积密度时,材料的质量是指填充在一定容器内的任意含水状态下的质量。但须注明含水率,其堆积体积是指所用容器的容积而言。因此,材料的堆积体积包含了颗粒内部的孔隙及颗粒之间的空隙。材料的堆积密度与材料的表观密度、堆积的紧密程度有关。在捣实状态下测定的堆积密度称为紧密堆积密度。 表观密度 英文名称: Apparent density

霍尔电流传感器工作原理

霍尔电流传感器工作原理 1、直放式(开环)电流传感器(CS系列) 当原边电流I P流过一根长导线时,在导线周围将产生一磁场,这一磁场的大小与流过导线的电流成正比,产生的磁场聚集在磁环内,通过磁环气隙中霍尔元件进行测量并放大输出,其输出电压V S精确的反映原边电流I P。一般的额定输出标定为4V。 2、磁平衡式(闭环)电流传感器(CSM系列) 磁平衡式电流传感器也称补偿式传感器,即原边电流Ip在聚磁环处所产生的磁场通过一个次级线圈电流所产生的磁场进行补偿,其补偿电流Is精确的反映原边电流Ip,从而使霍尔器件处于检测零磁通的工作状态。 具体工作过程为:当主回路有一电流通过时,在导线上产生的磁场被磁环聚集并感应到霍尔器件上,所产生的信号输出用于驱动功率管并使其导通,从而获得一个补偿电流Is。这一电流再通过多匝绕组产生磁场,该磁场与被测电流产生的磁场正好相反,因而补偿了原来的磁场,使霍尔器件的输出逐渐减小。当与Ip与匝数相乘所产生的磁场相等时,Is不再增加,这时的霍尔器件起到指示零磁通的作用,此时可以通过Is来测试Ip。当Ip变化时,平衡受到破坏,霍尔器件有信号输出,即重复上述过程重新达到平衡。被测电流的任何变化都会破坏这一平衡。一旦磁场失去平衡,霍尔器件就有信号输出。经功率放大后,立即就有相应的电流流过次级绕组以对失衡的磁场进行补偿。从磁场失衡到再次平衡,所需的时间理论上不到1μs,这是一个动态平衡的过程。因此,从宏观上看,次级的补偿电流安匝数在任何时间都与初级被测电流的安匝数相等。 3、霍尔电压(闭环)传感器(VSM系列)

霍尔电压传感器的工作原理与闭环式电流传感器相似,也是以磁平衡方式工作的。原边电压VP通过限流电阻Ri产生电流,流过原边线圈产生磁场,聚集在磁环内,通过磁环气隙中霍尔元件输出信号控制的补偿电流IS流过副边线圈产生的磁场进行补偿,其补偿电流IS精确的反映原边电压VP。 4、交流电流传感器(A-CS系列) 交流电流传感器主要测量交流信号灯电流。是将霍尔感应出的交流信号经过AC-DC及其他转换,变为0~4V、0~20mA(或4~20mA)的标准直流信号输出供各种系统使用。

细集料表观密度堆积密度及空隙率

细集料表观密度、堆积密度及空隙率 一、表观密度 1.仪器设备: 本试验用仪器设备如下: a)鼓风干燥箱:能使温度控制在(105±5)℃; b)天平:称量1000g,感量0.1g; c)容量瓶:500ml; d)干燥器、搪瓷盘、滴管、毛刷、温度计等。 2.实验步骤: 1)按规定取样方法取样,并将试样缩分至约660g,放在干燥箱中于(105±5)℃ 下烘干至恒重,待冷却至室温后,分为大致相等的两份备用。 2)称取试样300g,精确至0.1g。将试样装入容量瓶,注入冷开水至接近500ml 的刻度线处,用手旋转摇动容量瓶,使砂样充分摇动,排除气泡,塞紧瓶盖,静 置24h。然后用滴管小心加水至容量瓶500ml刻度处,塞紧瓶盖,擦干瓶外水分,称出其质量,精确至1g。 3)倒出瓶内水和试样,洗净容量瓶,再向容量瓶内注水(应与步骤“2)”水温 相差不超过2℃,并在15℃~25℃范围内)至500ml刻度处,塞紧瓶塞,擦干瓶 外水分,称出其质量,精确至1g。 注:在砂的表观密度试验过程中应测量并控制水的温度,试验的各项称量可在15℃~25℃的温度范围内进行。从试样加水静置的最后2h起直至 试验结束,其温度相差不应超过2℃。 3.结果计算与评定: 1)砂的表观密度按下式计算,精确至10kg/m3: 2)表观密度取两次试验结果的算术平均值,精确至10kg/m3;如两次试验结果之 差大于20kg/m3,应重新试验。 3)采用修约值比较法进行评定。

二、堆积密度与空隙率 1.仪器设备: 本试验用仪器设备如下: a)鼓风干燥箱:能使温度控制在(105±5)℃; b)天平:称量1000g,感量0.1g; c)容量筒:圆柱形金属筒,内经108mm,净高109mm,壁厚2mm,筒底厚约5mm,容积为1L; d)方孔筛:孔径为4.75mm的筛一只; e)垫棒:直径10mm,长500mm的圆钢; f)直尺、漏斗或料勺、搪瓷盘、毛刷等。 2.试验步骤: 1)按照规定取样方法取样,用搪瓷盘装取试样约3L,放在干燥箱中于(105±5)℃下烘干至恒重,待冷却至室温后,筛除大于4.75mm的颗粒,分为大致相等的两份备用。 2)松散堆积密度:取试样一份,用漏斗或料勺将试样从容量筒中心上方50mm 处徐徐倒入,让试样以自由落体落下,当容量筒上部试样呈椎体,且容量筒四周溢满时,即停止加料。然后用直尺沿筒口中心线向两边刮平(试验过程应防止触动容量筒),称出试样和容量筒总质量,精确至1g。 3)紧密堆积密度:取式样一份分为二次装入容量筒。装完第一层后(约计稍高于1/2),在筒底垫放一根直径为10mm的圆钢,将筒按住,左右交替击地面各25下。然后装入第二层,第二层装满后用同样方法颠实(但筒底所垫钢筋的方向与第一层时的方向垂直)后,再加试样直至超过筒口,然后用直尺沿筒口中心线向两边刮平,称出试样和容量筒总质量,精确至1g。 3.结果计算与评定: 1)松散或紧密堆积密度按下式计算,精确至10kg/m3: 2)空隙率按下式计算,精确至1%: 3)堆积密度取两次试验结果的算术平均值,精确至10kg/m3。空隙率取两次试验结果的算术平均值,精确至1%。

霍尔电流传感器的应用

霍尔电流传感器的应用 霍尔电流传感器广泛应用在变频调速装置、逆变装置、UPS电源、通信电源、电焊机、电力机车、变电站、数控机床、电解电镀、微机监测、电网监测等需要隔离检测电流的设施中以及新兴的太阳能、风能和地铁轨道信号、汽车电子等领域。 1、继电保护与测量: 在工业应用中,来自高压三相输电线路电流互感器的二次电流,如分别经三只霍尔电流传感器,按比例转换成毫伏电压输出,然后再经运算放大器放大及有源滤波,得到符合要求的电压信号,可送微机进行测量或处理。在这里使用霍尔电流传感器可以很方便地实现了无畸变、无延时的信号转换。 2、在直流自动控制调速系统中的应用: 在直流自动控制调速系统中,用霍尔电流电压传感器可以直接代替电流互感器,不仅动态响应好,还可实现对转子电流的最佳控制以及对晶闸管进行过载保护。 3、在逆变器中的应用: 在逆变器中,用霍尔电流传感器可进行接地故障检测、直接测和交流测的模拟量传感,以保证逆变器能安全工作。 4、在不间断电源中的应用: 在该应用中,用霍尔电流传感器进行控制,保证逆变电源正常工作。使用①霍尔电流传感器发出信号并进行反馈,以控制晶闸管的触发角,②霍尔电流传感器发出的信号控制逆变器,③

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简单易懂的霍尔电流传感器使用原理及相关霍尔型

简单易懂的霍尔电流传感器使用原理及相关霍 尔型 集团公司文件内部编码:(TTT-UUTT-MMYB-URTTY-ITTLTY-

1、开环(直放式)霍尔电流传感器 当原边电流I P 流过一根长导线时,在导线周围将产生一磁场,这一磁场的大小与流过导线的电流成正比,产生的磁场聚集在磁环内,通过磁环气隙中霍尔元件(如HG-302C) 进行测量并放大输出,其输出电压V S 精确的反映原边电流I P 。一般的额定输出标定为 4V。开环霍尔电流传感器的优点是结构简单,可靠性好,过载能力强,体积较小,开环式霍尔电流传感器一般线性度角差,且原边信号在上升和下降过程中副边输出会有不同。开环式霍尔电流传感器精度通常劣于1%。?一般开环电流传感器采用的霍尔是HG-106A,HG-106C,HG-166A,HG-302A,HG-302C,HG-362A,SS495A,SS495A1。 2、闭环(磁平衡式)霍尔电流传感器 磁平衡式电流传感器也称补偿式传感器,即原边电流Ip在聚磁环处所产生的磁场通过一个次级线圈电流所产生的磁场进行补偿,其补偿电流Is精确的反映原边电流Ip,从而使霍尔器件(如HW-300B,HW-302B)处于检测零磁通的工作状态。 当主回路有一电流通过时,在导线上产生的磁场被磁环聚集并感应到霍尔器件上,所产生的信号输出用于驱动功率管并使其导通,从而获得一个补偿电流Is。这一电流再通过多匝绕组产生磁场,该磁场与被测电流产生的磁场正好相反,因而补偿了原来的磁场,使霍尔器件的输出逐渐减小。当与Ip与匝数相乘所产生的磁场相等时,Is不再增加,这时的霍尔器件起到指示零磁通的作用,此时可以通过Is来测试Ip。当Ip变化时,平衡受到破坏,霍尔器件有信号输出,即重复上述过程重新达到平衡。被测电流的任何变化都会破坏这一平衡。一旦磁场失去平衡,霍尔器件(HW-300B,HW-302B)就有信号输出。经功率放大后,立即就有相应的电流流过次级绕组以对失衡的磁场进行补偿。从磁场失衡到再次平衡,所需的时间理论上不到1μs,是一个动态平衡的过程。因此,宏观上看,次级的补

简单易懂的霍尔电流传感器使用原理及相关霍尔型

简单易懂的霍尔电流传感器使用原理及相关霍尔型 This model paper was revised by the Standardization Office on December 10, 2020

简单易懂的霍尔电流传感器使用原理及相关霍尔型号推荐 1、开环(直放式)霍尔电流传感器 当原边电流I P 流过一根长导线时,在导线周围将产生一磁场,这一磁场的大小与流过导线的电流成正比,产生的磁场聚集在磁环内,通过磁环气隙中霍尔元件(如HG-302C) 进行测量并放大输出,其输出电压V S 精确的反映原边电流I P 。一般的额定输出标定为 4V。开环霍尔电流传感器的优点是结构简单,可靠性好,过载能力强,体积较小,开环式霍尔电流传感器一般线性度角差,且原边信号在上升和下降过程中副边输出会有不同。开环式霍尔电流传感器精度通常劣于1%。一般开环电流传感器采用的霍尔是HG-106A,HG-106C,HG-166A,HG-302A,HG-302C,HG-362A,SS495A,SS495A1。 2、闭环(磁平衡式)霍尔电流传感器 磁平衡式电流传感器也称补偿式传感器,即原边电流Ip在聚磁环处所产生的磁场通过一个次级线圈电流所产生的磁场进行补偿,其补偿电流Is精确的反映原边电流Ip,从而使霍尔器件(如HW-300B, HW-302B)处于检测零磁通的工作状态。 当主回路有一电流通过时,在导线上产生的磁场被磁环聚集并感应到霍尔器件上,所产生的信号输出用于驱动功率管并使其导通,从而获得一个补偿电流Is。这一电流再通过多匝绕组产生磁场,该磁场与被测电流产生的磁场正好相反,因而补偿了原来的磁场,使霍尔器件的输出逐渐减小。当与 Ip与匝数相乘所产生的磁场相等时,Is不再增加,这时的霍尔器件起到指示零磁通的作用,此时可以通过Is来测试Ip。当Ip变化时,平衡受到破坏,霍尔器件有信号输出,即重复上述过程重新达到平衡。被测电流的任何变化都会破坏这一平衡。一旦磁场失去平衡,霍尔器件(HW-300B,HW-302B)就有信号输出。经功率放大后,立即就有相应的电流流过次级绕组以对失衡的磁场进行补偿。从磁场失衡到再次平衡,所需的时间理论上不到1μs,是一个动态平衡的过程。因此,宏观上看,次级的补偿电流安匝数在任何时间都与初级被测电流的安匝数相等。一般来说闭环式电流传感器比开环电流传感器的精度更高,闭环霍尔电流传感器等特点是精度高,响应快,频带宽。闭环式霍尔电流传感器由于工作在零磁通状态,磁芯的非线性及磁滞效应不对输出造成影响,可以获得较好的线性度和较高的精度。闭环式霍尔电流传感器精度一般可达%。 闭环霍尔电流传感器一般采用的霍尔是HW-300B,HW-302B,HW-322B。

浅析霍尔电流传感器的应用

浅析霍尔电流传感器的应用 2006-6-26 15:35:00转自《仪器仪表交易网》供稿 一、前言伴随着城市人口和建设规模的扩大,各种用电设备的增多,用电量越来越大,城市的供电设备经常超负荷运转,用电环境变得越来越恶劣,对电源的“考验”越来越严重。据统计,每天,用电设备都要遭受120次左右各种的电源问题的侵扰,电子设备故障的60%来自电源.因此,电源问题的重要性日益凸显出来。原先作为配角,资金投入较少的电源越来越受到厂商和研究人员的重视,电源技术遂发展成为一门崭新的技术。 而今,小小的电源设备已经融合了越来越多的新技术。例如开关电源、硬开关、软开关、参数稳压、线性反馈稳压、磁放大器技术、数控调压、PWM、SPWM、电磁兼容等等。实际需求直接推动电源技术不断发展和进步,为了自动检测和显示电流,并在过流、过压等危害情况发生时具有自动保护功能和更高级的智能控制,具有传感检测、传感采样、传感保护的电源技术渐成趋势,检测电流或电压的传感器便应运而生并在我国开始受到广大电源设计者的青睐,本文主要介绍南京中旭电子科技有限公司的电流传感器。 二、电流传感器的工作原理 南京中旭电子科技有限公司的电流传感器可以测量各种类型的电流,从直流电到几十千赫兹的交流电,其所依据的工作原理主要是霍尔效应原理。(本文下面多以以零磁通闭环产品原理为例) 当原边导线经过电流传感器时,原边电流IP会产生磁力线,原边磁力线集中在磁芯气隙周围,内置在磁芯气隙中的霍尔电片可产生和原边磁力线成正比的,大小仅为几毫伏的感应电压,通过后续电子电路可把这个微小的信号转变成副边电流IS,并存在以下关系式:IS* NS= IP*NP 其中,IS—副边电流; IP—原边电流; NP—原边线圈匝数; NS—副边线圈匝数; NP/NS—匝数比,一般取NP=1。 电流传感器的输出信号是副边电流IS,它与输入信号(原边电流IP)成正比,IS一般很小,只有10~40 0mA。如果输出电流经过测量电阻RM,则可以得到一个与原边电流成正比的大小为几伏的电压输出信号。 2、传感器供电电压VA VA指电流传感器的供电电压,它必须在传感器所规定的范围内。超过此范围,传感器不能正常工作或可靠性降低,另外,传感器的供电电压VA又分为正极供电电压VA+和负极供电电压VA-。要注意单相供电的传感器,其供电电压VAmin是双相供电电压VAmin的2倍,所以其测量范围要相供高于双电的传感器。 3、测量范围Ipmax 测量范围指电流传感器可测量的最大电流值,测量范围一般高于标准额定值IPN。 三、电流传感器主要特性参数 1、标准额定值IPN和额定输出电流ISNIPN指电流传感器所能测试的标准额定值,用有效值表示(A.r. m.s),IPN的大小与传感器产品的型号有关。ISN指电流传感器额定输出电流,一般为10~400mA,当然根据某些型号具体可能会有所不同。 2、偏移电流ISO 偏移电流也叫残余电流或剩余电流,它主要是由霍尔元件或电子电路中运算放大器工作状态不稳造成的。电流传感器在生产时,在25℃,IP=0时的情况下,偏移电流已调至最小,但传感器在离开生产线时,都会产生一定大小的偏移电流。产品技术文档中提到的精度已考虑了偏移电流增加的影响。

霍尔电流传感器的应用

霍尔电流传感器的应用 霍尔电流传感器的应用 霍尔电流传感器的应用场合1、在逆变器中的应用:在逆变器中,用霍尔电流传感器可进行接地故障检测、直接侧和交流侧的模拟量传感,以保证逆变器能安全工作。2、在直流自动控制调速系统中的应用:在直流自动控制调速系统中,用霍尔电流电压传感器可以直接代替电流互感器,不仅动态响应好,还可实现对转子电流的最佳控制以及对晶闸管进行过载保护。3、继电保护与 测量:在工业应用中,来自高压三相输电线路电流互感器的二次电流,如分别经三只霍尔电流传感器,按比例转换成毫伏电压输出,然后再经运算放大器放大及有源滤波,得到符合要求的电压信号,可送微机进行测量或处理。在这里使用霍尔电流传感器可以很方便地实现了无畸变、无延时的信号转换。 4、在不间断电源中的应用:在该应用中,用霍尔电流传感器进行控制,保证逆变电源正常工作。使用霍尔电流传感器1 发出信号并进行反馈,以控制晶闸管的触发角,霍尔电流传感器2 发出的信号控制逆变器,霍尔电流传感器3 控制浮充电源。由于其响应速度快,霍尔电流传感器特别适用于计算机中的不间断电源。 5、在电子点焊机中的应用:在电子点焊机电源中,霍尔电流传感器起测量和控制作用。它的快速响应能再现电流、电压波形,将它们反馈到可控整流器A、B,可控制其输出。用斩波器给直流迭加上一个交流,可更精 确地控制电流。用霍尔电流传感器进行电流检测,既可测量电流的真正瞬时值,又不致引入损耗。 6、用于电车斩波器的控制:电车中的调速是由调整电压实现的。而将霍尔电流传感器和其它元件配合使用,并将传感器的所有信号输入控制系统,可确保电车正常工作。 7、在交流变频调速电机中的应用:用变频器来对交流电

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