Questions & Answers > Allowable Accuracy according to Metermans Handbook
Welcome back Peetey,
For Question #1: My past experience at a former utility was that our shop tester would balance the elements of the meter to be within 2% of each other.
The Meterman’s Handbook (10th Edition) page 504 states: Each separate stator in a multi stator meter must provide the same disk-driving torque with equal wattage applied to the individual stators for the meter to provide accurate registration when in service. It also speaks to the accuracy requirements of this test process as being determined by the local utility standards.
From the Instruction Manual by Sangamo Electric Co. (Springfield, IL) on pages 127-129 it states: Often, the test connection for a 2 stator meter provides for one element driving forward while the other element drives backwards and the balance adjustment is made there. Further reading in this instruction manual suggests that when testing the balance on a 3 element meter, the forward and backwards adjustment is made and these are balanced to the torque of the 3rd element.
For Question #2: My personal field test experience was that for an upscale demand test on an electro-mechanical register, the accuracy of the test had to be within 95% of the calculated upscale value.
I can find nothing in the Meterman’s Handbooks (both 9th & 10th Editions) that references an allowable deviation between actual demand and what the calculated value is.
Thanks for your questions. Hope this provides some help.
Be Safe All Ways,
Brad
Brad
I have a quick couple of questions. #1 when doing balance testing on a mechanical meter, what is the allowable deviation in accuracy between stators? When I do a demand test what is the allowable deviation between what demand actually ran and what the calculated value is ? I am curious what the latest edition of the Metermans Handbook says and what metermen generally say. Thanks in advance...
Peetey