Alpha Technologies USM2.5 Status Monitoring Module - Manual (Page 24)

3. Troubleshooting
24 018-041-C0-003 Rev. C
3.1 Important Troubleshooting Notes, continued
-
+
Battery
1x
-
+
Battery
2x
-
+
Battery
3x
-
+
Battery
4x
Black (neg) wire
to power supply
Red (pos) wire to
power supply
NEG
Vbatt 1x +12V
Vbatt 2x +24V
Vbatt 3x +36V
Vbatt 4x +48V
Figure 3-1 Battery String Example
If there are two power supplies in the same enclosure, make sure that the interface cable from
the generator ECM is connected to the correct embedded transponder.
4. Battery Voltage Jumper: Verify that the battery voltage jumper block is in the correct position:
• The jumper will be installed in the bottom position for 36VDC battery systems (shorting the
bottom two rows of pins, and with the top row of pins exposed)
• The jumper will be installed in the top position for 48VDC battery systems (shorting the top
two rows of pins, and with the bottom row of pins exposed).
Use extreme care when removing the jumper – lift the jumper only, don’t pry the pin assembly
off the PC board.
5. Battery Voltage Sensing: Verify the battery sensing cables are connected correctly – battery
polarity is critical. The battery numbering / labeling conforms to the requirements of the SCTE
HMS standard. (Refer to section 1.3, Battery Monitor Connections.) The battery numbering
shown in Acterna’s CheetahNet display will be as listed in the manual.
• Each string is labeled A, B, C, or D, shown as “x” below. Not all battery sensing wires will
be present in all harnesses. For example, in a 2 string system, there may only be one
NEG wire - connect to either string’s battery # 1 negative post.