PPI Power Sample Exam 1: Morning Session - Ques. # 15

Professional Engineer & PE Exam Forum

Help Support Professional Engineer & PE Exam Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

bripgilb

Well-known member
Joined
Sep 22, 2017
Messages
47
Reaction score
10
Gentlemen,

This is my first time posting on forums and first time on EngineeringBoards.

I'm studying for the Power PE Exam now. Take it in Oct.

Ran across this problem in Camara PPI Practice Exam Book.   The question is about a d'Arsonval meter.  I did not know how to do the problem.  I figured the answer was 9750 ohm.  

When looking at the solution it states that "an additional 1.5% error can occur in the external resistance".  Where does this comment come from?

Best regards,

bripgilb

IMG_4764.jpg

IMG_4765.jpg

IMG_4766.jpg

 
Ok... So I think I understand.

(%accuracy of Rext) = ((%accuracy total) - (%accuracy of Rcoil))

1.5% = (2.5%-1%)

Thanks for anyone who looks at this!

 
Back
Top