Voltage Reduction Device (Vrd); Vrd Specification; Vrd Maintenance - Thermal Arc ARCMASTER 185 AC/DC Operating Manual

11.01 VRD SPECIFICATION

Description
VRD Open Circuit Voltage
VRD Resistance
VRD Turn OFF Time

11.02 VRD MAINTENANCE

Routine inspection and testing (power source):
An inspection of the power source, an insulation resistance test and an earth resistance test should be carried out.
a. For transportable equipment, at least once every 3 months.
b. For fixed equipment, at least once every 12 months.
The owners of the equipment shall keep a suitable record of the periodic tests.
A transportable power source is any equipment that is not permanently connected and fixed in the position
in which it is operated.
In addition to the above tests and specifically in relation to the VRD fitted to this machine, the following periodic tests
should also be conducted by an accredited Thermal Arc service agent.
VRD Open Circuit Voltage
VRD Turn ON Resistance
VRD Turn OFF Time
If this equipment is used in a location or an environment with a high risk of electrocution then the above tests should
be carried out prior to entering this location.
February 20, 2006
SECTION 11:

VOLTAGE REDUCTION DEVICE (VRD)

ArcMaster
185AC/DC
15.3 to 19.8V
148 to 193 ohms The required resistance between
0.2 to 0.3
seconds
Table 11-1: VRD Specification
Description
Table 11-2: Periodic Tests
Notes
Open circuit voltage between
welding terminals.
welding terminals to turn ON the
welding power.
The time taken to turn OFF the
welding power once the welding
current has stopped.
NOTE
IEC 60974-1 Requirements
Less than 20V; at Vin=230V
Less than 200 ohms
Less than 0.3 seconds
ARCMASTER 185 AC/DC
11-1