Thermal Dynamics Ultra-Cut 300 XT, Operating Instructions Manual

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ULTRA-CUT 400 XT
A-50 APPENDIX Manual 0-5275
Arc starter with Spark Gap (Auto-Cut)
No spark at spark gap
1. Check that spark gap is set for 0.062” +/- 0.002”. If gap is too high there may not be enough voltage from
T1 to fire the gap.
2. Check for power to the high frequency (HF) transformer (T2 in AC 200 XT; T1 in GCM1000XT) during the 15
seconds following prefow (ignition phase). Arc starter power comes through the rear panel circuit breaker
CB4, make sure it isn’t tripped.
a. For the GCM1000XT (AC300XT) 120 VAC from J59-7 & 9 on the power supply rear panel connects to
J58-7 & 9 on the GCM 1000XT. See diagram below. From J58 on the GCM1000XT it goes directly to the
line filter and passes through the filter to primary of T1. During the ignition phase, check for 120 VAC
on the T1 side of the line filter.
b. For AC200XT the HF transformer T2 has insulated Faston (also known as push on , stab-on, spade, etc.)
on its primary wires. Disconnect these and measure for 120 VAC on the harness side during ignition
phase.
3. If 120 VAC not present go to step 4.
a. If 120 VAC is present and still no spark, T1 (T2 in AC200XT) may be bad. Remove power and measure
resistance of T1 (T2 in AC200XT) primary and secondary. The primary should measure about 3-7 ohms.
The secondary about 25-35 K ohms. If either measurement not correct replace T1 (T2 in AC200XT).
b. If T1 (T2 in AC200XT) measures OK, check for shorted capacitors C1-C3 (very unlikely).
4. No 120 VAC to T1 (T2 in AC200XT) primary during the ignition phase (15 seconds following Preflow) check
for 120 VAC into the line filter (GCM1000XT only). If it’s there replace the filter. If 120 VAC isn’t present at
the line filter or if this is an AC 200XT go to step 5 in section Either Arc Starter below.
Arc starter without Spark Gap (Ultra-Cut)
1. Check for power to the RAS 1000XT’s Ignition Module during the 15 seconds following preflow (ignition
phase). Arc starter power comes through the rear panel circuit breaker CB4, make sure it isn’t tripped.
a. During the ignition phase, measure for 120 VAC at the input terminals marked 120 VAC on the Ignition
module, a gray rectangular box with screw terminals on one side.
WARNING
Do not let the meter probes (or your hands) come in contact with the other terminals
marked Hb and Ho or the other end of the wires connected to them. These can have
10,000 volt pulses which can cause physical harm and will damage your meter.