CHOWEL PATC--150A-EU, Instruction Manual

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CHOWEL / PATC-150A-EU
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6. Description
6-1 General description
The PATC-150A-EU Welding Transformer and Controller is housed in a steel case
that is sealed against ingress of moisture and dirt. The case contains the complete
welding control system which consists power thyristor.
The welding Control is connected across one phase main electric supply and to
the welding machine.
Electrical supply cables are enter the top side of the SCR box.
Control cables are enter the right side of Timer box.
At the bottom side of Timer box, there is communication connector for attaching
the control signal lead from a TB-30 or RB-10.
6-2 Mechanical Description
The power components are located on the SCR box. They are covered by clear
plastic panels that provided protection against electric shock. Those panel should
be removed only when the electric supply has been disconnected externally. Once
they are removed, access is gained for marking connections and for carrying out
replacements and repairs.
To avoid electric shock, properly earth the PATC-150A-EU frame.
An earth terminal, it provide to connection on right side of transformer body.
6-3 Welding control Description
The main supply is applied direct to the terminal 01, 02 which connect direct to
the thyristors.
The thyristors are cooled by water that is externally pumped through the heatsink.
Chapter 3, Specifications, give the requirements specification of this supply.
A temperature sensor on the thyristor trips out at excessive temperatures, supplying
a signal via the thyristor control cable to the timer unit.
The hose connectors(nipples) are earth which ensures that water leaving the
welding control is electrically safe (provided the electrical resistivity requirement of
the water is met).