ARMY TM 10-4610-309-14
MARINE CORPS TM10802A-14/1
0035 00
TACTICAL WATER PURIFICATION SYSTEM (TWPS)
TROUBLESHOOTING PROCEDURES
UNIT TROUBLESHOOTING - TWPS CONTROL SYSTEMS
Table 2. OCP Display and Instrument Loop Troubleshooting Continued.
ITEM
MALFUNCTION
POSSIBLE CAUSES
CORRECTIVE ACTION
7
TMP cannot be adjusted to
3)
If there is no voltage, set the Main
cont
zero (with TWPS properly in
breaker to OFF. Remove the wires and
STANDBY).
check for resistance. If there is an open
circuit, replace the MF Transmembrane
Or
Zero Adjust (1000 Ohm) potentiometer
TMP reading is suddenly very
and it changes as the MF
high and the TMP High alarm
Transmembrane Zero Adjust is
is on (continued).
changed, replace the Slot 11 input card
PLC Slot 12 input card failure
If other faults have not been indicated,
replace the Slot 12 input card (WP 0060).
8
RO Feed Pressure display
PLC Slot 9 output card failure or display
Conduct BIT test and stop at the display test.
does not change as the Main
failure.
If the display does not count up, refer to Item
Pressure control valve is
2 above.
closed.
Pressure transmitter PT-302 or PLC Slot
Open the OCP display panel to expose the
12 input card failure, RO feed pressure
sub-panel. Locate the Slot 12 input card
reading high.
replace card.
1) Remove IN2+ wire and turn terminal
screw back in. Measure the mA (4-
20mA range) between the wire and the
terminal.
2) If reading is approximately 20mA,
perform continuity checks with PDP
main breaker OFF. Perform continuity
check on wiring from input card to
connector pins. Check for short circuit
between pins A and B with connector
disconnected from transducer and both
wires disconnected from input card.
Replace cable if short circuit found.
3) If short circuit not found, replace PT-
302.
4) If problem re-occurs replace Slot 12
input card.
Pressure transmitter PT-302 or PLC Slot
Open the OCP display panel to expose the
12 input card failure, RO feed pressure
sub-panel. Locate the Slot 12 input card
reading low.
replace card.
1) Remove IN2+ wire and turn terminal
screw back in. Measure the mA (4-
20mA range) between the wire and the
terminal.
2) If reading is still less than 3.75mA,
replace the transmitter (WP 0062).
3) If reading is still less thank 3.75mA after
replacing the transmitter, check the
connector, cable, and panel wiring for
open circuits. Perform these checks
with the PDP OFF.
0035 00-9
