Section 11: voltage reduction device (vrd), 01 vrd specification, 02 vrd maintenance – Tweco 200 ACDC Arcmaster(April2006) User Manual
Page 57: Section 11, Voltage reduction device (vrd) -1, 01 vrd specification -1 11.02 vrd maintenance -1, Arcmaster 200 ac/dc

ARCMASTER 200 AC/DC
April 13, 2006
11-1
SECTION 11:
VOLTAGE REDUCTION DEVICE (VRD)
11.01 VRD SPECIFICATION
ArcMaster
Description
200 AC/DC
Notes
VRD Open Circuit Voltage
15.3 to 19.8V
Open circuit voltage between welding
terminals.
VRD Resistance
148 to 193 ohms The required resistance between
welding terminals to turn ON the
welding power.
VRD Turn OFF Time
0.2 to 0.3
seconds
The time taken to turn OFF the welding
power once the welding current has
stopped.
Table 11-1: VRD Specification
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.
NOTE
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.
Description
IEC 60974-1 Requirements
VRD Open Circuit Voltage
Less than 20V; at Vin=230V
VRD Turn ON Resistance
Less than 200 ohms
VRD Turn OFF Time
Less than 0.3 seconds
Table 11-2: Periodic Tests
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.