IGEA launches first Belarusian VRD
The Institute of Mining Electrical Engineering and Automation launched the first domestic open circuit voltage reduction device (VRD) for arc welding power supply.
Shielded metal arc welding (SMAW) is the most common arc welding technique, however, welding power source OCV may pose hazard to life at certain values and environment conditions.
To provide electrical safety of arc welding, an arc welding power supply open circuit voltage reduction device (VRD) shall be used - BSNKh-630 by the IGEA.
The VRD shall be used for arc welding in any environment, including highly hazardous: inside metal tanks, in wells, tunnels, shafts, boilers, on floating tanks, inside vessel sections, in high humidity ambient, etc.
To provide work safety, the VRD isolates the welding rod holder from the welder and feeds the welding rod with effective voltage not above 12V from the VRD circuit.
Advantages of our device:
No need for mains power supply: the VRD consumes the OCV of the connected AC or DC welding power supply.
Ambient temperature: -40°C to 40°C
High-power thyristor module as a switching element for high energy and thermal cycle resistance
Stable short-circuit impedance sensitivity irrespective of the welding power supply OCV
While securing the welder operator, the VRD interferes welding not, arc striking is always reliable including on oxidised or contaminated surfaces.
The circuit operating speed is such that an integrated VRD has no effect on the welding process.
According to the tests, the IGEA VRD performance is better than required by GOST 12.2.007.8:
Contact resistance between the ground terminal and metal casing of the VRD is below 0.05Ω, lower OCV – 7.9V
Measured VRD triggering threshold - 2970Ω
Measured limited OCV settling time after welding circuit opening – 0.13s
Measured output voltage recovery time after welding circuit closing – 0.02s