ESAB 100i Service Manual page 104

iSERIES 100 /200 /300 /400
In addition to the pressure test or in place of it if you don't have a gauge, determine if the flow returning from
the torch (the flow that passes through the FS1), is greater than the required minimum. With the unit switched
off remove the return hose from the back of the power supply. Place it in a container of a known volume. Turn
the unit on and let the pump run exactly 30 seconds. It should pump at least 3/8 gal. (1.4 l). Use a larger con-
tainer in case the flow is greater and it overflows.
If the flow is lower than 0.75 GPM (0.25 GPM for PAK200i):
• Look for restrictions such as sharp bends or something pinching the coolant hoses or torch leads.
• Other possibilities are the bypass valve has been adjusted wrong (someone may have turned the adjust-
ment screw) see pressure test/adjustment above
• The pump is worn out (may be the case with an older unit).
Coolant flow is correct but system doesn't detect it due to defective components:
• Defective or disconnected FS1 flow switch.
• Relay board.
• CCM.
Flow Switch FS1 disconnected – FS1 comes with wire about 1 ft. long and a connector that connects to a 3 wire
harness. This could be disconnected at either end, J74 or J5 on the relay board.
Defective FS1– The flow switch, normally open, closes when flow through it exceeds 0.75 GPM, could be open.
Easiest place to measure the switch is at the J5 harness connector that plugs into the Pilot board. Assuming you
have previously determined flow is sufficient, disconnect J5 from the Pilot board, start the unit so the coolant
is flowing and measure continuity between the 2 pins of J5.
• If there is no continuity either the switch is open or the harness between J5 and J74 at FS1 is open.
• If there is continuity between the J5 pins with sufficient coolant flow then either relay board or the CCM
is faulty.
405 Low Coolant Level Warning
If the coolant level becomes low while cutting it is not necessary to immediately stop the cut as there is still
enough coolant to continue so we display E405 as a warning. Once the cut stops if the coolant is still low the
display changes to E401 and prevents starting another cut. Refer to the section for code 401 for troubleshooting.
406 Coolant Flow Low Warning
This code is a warning, it does not prevent cutting but if it persists the cause should be investigated. iSeries
XT units, in addition to a coolant flow switch, include a turbine flow sensor FL1, referred to in the plumbing
diagram as a "bubble sensor", with a pulse output that accurately measures coolant flow and in addition can
detect the presence of gas bubbles in the coolant. Gas bubbles from leaking seals in the torch or hose fittings
have been proven to reduce consumable life. This code is a warning, it does not prevent cutting but if it persists
the cause should be investigated.
407 Coolant Overheated due to High Ambient
As described in the section for codes 259-264 the CCM measures the ambient temperature using sensor TS2 and,
like with the inverters, if the coolant is over temperature we first check the ambient and if it is above 40 deg C
we attribute the cause of the coolant over temperature to high ambient and of course the solution is to lower
the ambient or reduce the duty cycle.
The other possibility is the ambient measuring circuit is defective and the coolant is overheated. In that case
you would have to go to the section for code 403 to find the cause of the coolant overheating and go to section
for codes 259-264 to determine what is wrong with the TS2 circuit.
A-84 APPENDIX Manual 0560956456