Technical

• The weakest part of an electrical circuit is its earthing integrity and hence the most important aspect from an electrical safety perspective. Yet once designed & installed, we often forget to verify its integrity! When was the last time you verified the integrity of the earth stake at your home?
• In truth, even we in the industry overlook it yet frontline protective devices RCD’s/RCBO’s, require a low impedance earth path in order to provide electrical protection and when not present, electrical safety can be compromised.                 
• A ‘good/low impedance earth’ may be compromised by many factors including corrosion, hot joints and aging installations but by far the most variable and overlooked is the ground itself. 
• Soil types such as sandy/rocky environments, concrete and bitumen pose a real problem making a low impedance environment difficult and at worst impossible to achieve. Add in moisture and environmental changes and the problem is exacerbated.
• Unearthed or IT systems are also problematic for RCD’s due to lack of an earth-path and the 1st and 2nd fault scenario. Although widely regarded as the safest earthing system, they are not widely used as a result.                            
• Our RVT-VMD device is designed to accompany any RCD/RCBO and provided 'additional layers’ of electrical protection. 
• Our RVT-VMD device enables enhanced electrical protection within the TN (MEN), TT earthed systems and uniquely IT unearthed systems. Importantly, our Technology enables protection against the non-dangerous IT 1st fault condition. This allows the ‘Bird on the Wire’ concept to become a reality and effectively removing the human from becoming part of the electrical circuit.
• When the RVT-VMD device is operating in an IT or floating environment, the device essentially becomes the centre tap/reference point of the transformer, being held at zero volts. 
• The RVT-VMD is detecting a voltage rise from an insulation breakdown on either L1 or L2 onto the frame being protected. When a voltage above the trigger level of 43V is detected, the device causes a 33mA imbalance across the RCD which isolates the circuit. When this occurs, 8mA of fault current flows with isolation occuring in under 20mSec.
• The RVT_VMD device is an electrically connected ‘add-on’, creating an imbalance across the RCD/RCBO when a voltage leakage to earth/frame is detected, complementing RCD’s in ‘bad earth’ environments, un-earthed installations or applications including portable generators, power inverters and UPS. 
• Other benefits of RVT-VMD include ‘Polarity Sensitive’ and protection against ‘loss of neutral integrity’ on the supply side of the MEN point, the biggest cause of electrical shock in Australia.
• Our Residual Voltage Tehnology (RVT-VMD) device mitigates electrical safety risk, especially personal protection, by ‘monitoring the earth/frame’ for a broader range of fault detection.  

For further information email us at;  Info@wwest.com.au