Hypertherm MAXPRO200 Preventive Maintenance Program - Manual (Page 14)

10 MAXPRO200 Preventive Maintenance Program Instruction Manual 808800
2. Disconnect the return hose from the top of the coolant tank. Push the connector-collar toward the fitting, and pull the
hose away from the fitting This will release the coolant hose. No tools required. Put the end of the return hose into a
4 liter (1 gallon) container.
3. You will need to enable the flow function before the count reaches 5 in the 3-digit display. Turn ON the power and
press and release the current knob twice until the flow function is enabled. Turn OFF the power after the coolant
flows for 30 seconds.
4. Measure the amount of coolant in the container. There should be about 2 liters (0.5 gallon). If there is less than 1 liter
(0.25 gallon) there may be a restriction in the coolant system or a problem with the pump or flow sensor.
5. Verify the flow sensor output by measuring the flow output (in frequency) at the control board. Measure the
Frequency on J21 pin 3 (pulse) and pin 2 (ground). Once you have the frequency use the chart below to get the flow
sensors measured flow rate. If this number differs more than 0.8 lpm (0.2 gpm) from your bucket test, the flow sensor
may need to be replaced.