Arcon 10310, Operating Manual

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6. ELECTRICAL SPECIFICATIONS & DIAGRAMS
6.1 General Information
Circuit breaker
The 3 phase elecric input power is connected to circuit breaker (K). When the welder is used for
240 V single phase, the brown conductor is not connected. When the correct phases are
connected, the fan will start and run for a few minutes and then stop. The fan will start every
time the circuit breaker is operated.
CF Assembly
The CF assembly has three functions: a six-pulse rectifier, supression of electro- magnetic
interference (EMI) and supression of voltage surges entering the welding machine from the
power lines.
Rectifier
The input rectifier consists of the power diodes CR1 to CR6. The maximum voltage over the
diodes are upgraded to 1400 V, making the diodes and MOV’s a very reliable design solution.
MOVs
(Metal Oxide Varistors)
The Workhorse 300MS not only uses MOVs from phase to ground (RV1, RV3, and RV6), but
also between phases (RV2, RV4, and RV5). The phase to ground MOV protects the diode from
a voltage surge between phase and ground. MOVs RV2, RV4, and RV6 protect
The Workhorse
phase to phase, and RV1 to RV6 protect
The Workhorse
from high voltage surges. The
machine is also protected from more powerful current surges by R7, withstanding surges of up to
40,000 Amps.
EMI
(Electro Magnetic Interference)
The Electro Magnetic Interference from the inverter is supressed by two capacitors in paralell
between phase and neutral. These capacitors (C2,C3,C5,C6,C7 and C8) must be of type X to be
allowed to be connected between phases and also to comply with European CE norms.
The X capacitors are connected to a common point, making it a virtual neutral. This point is
connected to safety ground via two ”Y” capacitors and one 33-ohm resistor. The type ”Y”
capacitors must be the high reliability ( HiRel ) version because a malfunction could energize the
ground wire.
Although the case
of The Workhorse
is made of non-conductive glassfiber-reinforced Polyester,
the strength and durability of the case is greater than most steel or aluminum housings.
The 480 V version of
The Workhorse
must have two Y capacitors in series to comply with the
CE norms and be allowed to be sold to the European Community (EC). The T1 auxiliary
transformer is connected to two of the 3 phases. It is protected by an internal thermal switch (t)
The surge resistors (R1 and R2) limits the current through the SCRs should they fire at the same
time. The circuit breaker limits the time the current is flowing through the resistors. Together they
protect the SCR from destructive current should a cross firing of the SCRs occurs.