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ecubed
October 8, 2019, 12:46 PM
One indication that a vented lead-acid battery is in trouble is when its internal impedance increases ____ above its as installed impedance:

5%
20%
30%
45%
Mark For Later Review

according to 7.18.1.1.D.6, which is referenced in the hints, the correct answer should 25%

sfarhang
October 16, 2019, 10:08 AM
One indication that a vented lead-acid battery is in trouble is when its internal impedance increases ____ above its as installed impedance:

5%
20%
30%
45%
Mark For Later Review

according to 7.18.1.1.D.6, which is referenced in the hints, the correct answer should 25%

20% is correct answer among those choices.

ecubed
November 2, 2019, 03:22 PM
20% is correct answer

Where can I reference this answer? I looked in both the ATS and MTS, under 7.18.1.1.D.6, which was the referenced hint and it says "cell internal ohmic values(resistance, impedance, or conductance) shall not vary by more than 25% between identical cells that are in a fully charged state." Either the reference is wrong or the answer.

testguy
November 2, 2019, 04:54 PM
Where can I reference this answer? I looked in both the ATS and MTS, under 7.18.1.1.D.6, which was the referenced hint and it says "cell internal ohmic values(resistance, impedance, or conductance) shall not vary by more than 25% between identical cells that are in a fully charged state." Either the reference is wrong or the answer.

Answer was found to be incorrectly entered into the database and has been changed to reflect the most recent NETA standard. Thank you for reporting.

sfarhang
November 2, 2019, 09:42 PM
Where can I reference this answer? I looked in both the ATS and MTS, under 7.18.1.1.D.6, which was the referenced hint and it says "cell internal ohmic values(resistance, impedance, or conductance) shall not vary by more than 25% between identical cells that are in a fully charged state." Either the reference is wrong or the answer.

… Shall not vary by more than 25% but among the following choices:
5%
20%
30%
45%
The best answer is 20%

mbaxter1
November 3, 2019, 07:12 PM
… Shall not vary by more than 25% but among the following choices:
5%
20%
30%
45%
The best answer is 20%

30 is closer to 25 than 20.