Tweco PAK 200i - Manual (Page 149)

PAK 200i
Manual 0-5335 APPENDIX A-69
Troubleshooting:
1. Confirm visually that the level switch float is below the coolant, if not add more coolant to the tank.
2. Check J7 on the Relay board.
a. If properly connected remove J7 and check continuity between pins 2 and 4 (pins 2 & 3 of J71 on the
switch itself).
b. If no continuity at J71 on the switch, if it is still open, replace the switch.
3. If there was continuity at J7 plug it back in and measure voltage on pin 9 of the 40 pin ribbon cable (Relay
board J4 to CCM J23). Common is TP1 on either the Relay or the I/O board.
a. Pin 9 should be high, about +10 to +15V. If it’s not the relay board is bad or the ribbon cable is shorted.
b. To test the ribbon cable remove both ends, J4 on the Relay board and J23 on the I/O board and measure
from pin 9 of the ribbon cable to both pin 8 and pin 10 of the cable. Both should be open. If not replace
the ribbon cable. Otherwise it’s the Relay board.
4. If pin 9 of the 40 pin ribbon cable was high in step 3.a the CCM is defective.
402 Low coolant Flow
The flow switch FS1 is positioned in series with the radiator where it measures the flow returning from the
torch. The flow switch serves two purposes, one to insure there is adequate flow for cooling needs and two,
it insures the torch consumables are in place so the negative output of the power supply is not exposed. This
function is called “Parts in Place” or PIP. The output cannot be enabled if parts are not in place. The normally
open flow switch requires 0.7 GPM (2.65 liter/min.) +/- about 10% to close. 0.5 GPM (1.9 l/m) for the PAK 200i.
When the system is turned on and enabled and fails to achieve proper coolant flow after 4 minutes code 404
will be set. Getting code 402 means it initially had enough flow but something has caused the flow to be re-
duced. Listed here are things that might happen during cutting to cause reduced flow. For other causes like
component failures refer to code 404.
Possible causes for low flow:
• Coolant filter clogged.
• Flow bypass valve incorrect adjustment or defective. Call the factory for instructions.
• Defective pump.
• Coolant supply or return hose twisted or pinched reducing flow.
If coolant flow is not low but code is being set, possible causes:
• Flow switch disconnected or defective.
• Relay PCB.
• CCM.
Troubleshooting:
1. First note whether the fault is an “E” meaning it’s currently low or an “L” meaning it was low but isn’t now.
Flow that remains low could indicate a failed component or a blockage such as clogged filter or pinched
hose. It also means you should be able to measure the flow to determine if it is really low or the sensor has
a problem.
2. First recycle power. If flow is still low or a component is defective the code should change to 404. Go to
that section for further troubleshooting.
3. If after recycling power there is no code, continue cutting to see if it occurs again. Take note of when it oc-
curs, for example if it’s with the torch at one end of the table, perhaps the leads get pinched there? In any
case go to code 404 section for more information.