CIGWELD 250i Transmig, Service Manual

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TROUBLE SHOOTING TRANSMIG 250i
Manual 0-5188 6-5 TROUBLE SHOOTING
B. Insulation Resistance
Minimum insulation resistance for in-service Cigweld Inverter Power Sources shall be measured at a volt-
age of 500V between the parts referred to in Table 6-2 below. Power sources that do not meet the insulation
resistance requirements set out below shall be withdrawn from service and not returned until repairs have
been performed such that the requirements outlined below are met.
Components to be Tested
Minimum Insulation
Resistance (M Ω )
Input circuit (including any connected control circuits) to welding circuit
(including any connected control circuits)
5
All circuits to exposed conductive parts
2.5
Welding circuit (including any connected control circuits) to any auxiliary
circuit which operates at a voltage exceeding extra low voltage
10
Welding circuit (including any connected control circuits) to any auxiliary
circuit which operates at a voltage not exceeding extra low voltage
1
Separate welding circuit to separate welding circuit
1
Table 6-2: Minimum Insulation Resistance Requirements: Cigweld Inverter Power Sources
C. Earthing/Grounding
The resistance shall not exceed 1Ω between any metal of a power source where such metal is required to be
earthed, and -
1. The earth terminal of a fixed power source; or
2. The earth terminal of the associated plug of a transportable power source
Note that due to the dangers of stray output currents damaging fixed wiring, the integrity of fixed wiring
supplying Cigweld welding power sources should be inspected by a licensed electrical worker in accordance
with the requirements below -
1. For outlets/wiring and associated accessories supplying transportable equipment - at least once every
3 months; and
2. For outlets/wiring and associated accessories supplying fixed equipment - at least once every 12 months.
D. Voltage Reduction Device (VRD)
Units fitted with VRD's, shall have the periodic tests outlined in Table 6-3 below conducted by an accredited
CIGWELD service provider. Testing shall be conducted at intervals as outlined below -
1. For transportable equipment, at least once every 3 months; and
2. For fixed equipment, at least once every 12 months.
Description Required Parameters
VRD Open Circuit Voltage Less than 35V; at nominal input voltage
VRD Turn ON Resistance Less than 200 ohms
VRD Turn OFF Time Less than 0.3 seconds
Table 6-3: VRD Periodic Tests