Specifications

Chapter 2 Service
Troubleshooting the Counter
154 Assembly-Level Service Guide
Battery Operation
When AC power is applied to the counter, the +15 VDC from the counter’s
standard AC power supply is routed through the battery connector cable
and back to the motherboard, where several switching power supplies are
used to provide the other DC circuit voltages needed by the counter
measurement circuits (see Table 2-6 above).
When AC voltage is disconnected or lost from the counter, the battery (if
turned ON) applies its own approximately +10 VDC to +12 VDC to the
motherboard. This voltage is sufficient for the switching supplies to
continue operation.
Preliminary Steps
NOTE Before proceeding, follow all the ESD steps as outlined in “Do
This First” on page 171 of this service guide.
1 Remove the instrument cover as follows:
NOTE Refer as necessary to the illustrations in the section “To Remove
the Cover and Rear Bezel” on page 173 of this service guide.
2 Remove the AC power cord from the counter and disconnect any
signal or interface cables present.
3 To remove the counter handle, rotate the handle to the vertical
(90 degree) position and pull outward on the two side arms.
4 Using a T20 TORX screwdriver, loosen the two TORX screws
securing the rear panel bezel.
5 Slide the outside cover of the counter to the rear and remove the
cover.
6 Move the Option 300 Internal Battery DC Power Assembly into its
service position as follows (refer to the procedure in “To Remove
the Internal DC Battery Assembly (Option 300)” on page 175 , as
needed):