again. if the needle will not zero after you
Using the Ohms Scale
have replaced the batteries, turn the meter in
When troubleshooting an electrical malfunc-
Zero the Meter. To obtain an accurate reading, you
tion or performing electrical maintenance,
must first adjust the meter so that when there is zero
ALWAYS disconnect Intervehicular electrical
resistance, the needle gives a reading of zero. Use the
cable from semitrailer, and negative battery
appropriate procedure below for the type of meter in your
cables at batteries. Failure to follow this warn-
ing may create a spark and explosion, result-
ing in serious injury or death to personnel.
(1) AN/URM-105. Use the procedure shown in
if the needle will not zero properly, replace
(2) TS-352 B/U. Use the procedure shown in
the batteries and try the zeroing procedure
SET SELECTOR SWITCH TO Xl
NOW ZERO THE METER.
TOUCH THE 2 PROBES
IF NEEDLE WILL NOT "ZERO" REPLACE THE BATTERIES.
IF THE NEEDLE STILL WILL NOT "ZERO" AFTER REPLAC-
ING THE BATTERIES, TURN THE METER IN FOR REPAIR,
Figure 4-5. Zeroing the AN/URM-105.