Hypertherm Powermax45 Service Manual - Manual (Page 102)

TroubleshooTing and sysTem TesTs
5-26
powermax
45 Service Manual
Test 6 – plasma start
Verify that the control board LED is receiving a valid start signal.
1. With the power ON, look at the Start LED on the control board. It should illuminate whenever the torch is
activated.
2. Set the ON/OFF switch to OFF (O). Check the resistance between pins 2 and 3 of J10 on the power board.
With the trigger or start signal engaged, the resistance should be 10 Ω or less. With the trigger or start signal
disengaged, the circuit should read as approximately 3 kΩ. If this test fails, check the torch’s start switch and the
torch wires.
NOTE: If the torch will not fire after completing this test, verify that J10 is connected properly – that the pins are
not offset and the connector is not backwards.
3. Set the ON/OFF switch to ON (I). Measure pin 16 of J7 (or J8 for 400 V CE and 480 V CSA power supplies) to
ground (see Test 2 – power board voltage checks on page 5-19). It should measure as 0 VDC for an open circuit
or 3.2 VDC for a closed circuit. If the values are not correct, replace the power board.
CAUTIoN
While testing, remove the consumables to avoid accidentally firing the torch.
TP 19
W
- + - +
TP 18
R
TP 17
B
192 VDC 192 VDC
J10
J7 (or J8)
J10