Ground Faults represent 90% of all electrical faults so having an effective ground fault detection system is vital to every facility. Since ground faults are the cause of so many faults, having a system to quickly locate the ground fault is essential to fixing the cause of the fault.

Detection

Ground indicator lights are the minimum requirement of the Canadian Electrical Code ( Rule 10-106(2) ). This is by no means an ideal setup because they require daily inspection. An ideal setup would use a Power Monitoring system to send an email, page, or SMS message to the appropriate people to take care of the issue.

can supply, install and commission the Neutral Voltage & Current Monitoring system on any distribution system as follows:

• Install a current monitoring CT and voltage monitoring circuit and tie them either into existing energey management system or supply and install suitable power monitor.
• Configure the Power Monitor and the Energy Management software to alarm on neutral to ground voltage and neutral current present. The alarm can be displayed using the energy management software or any other SCADA/HMI system present in your facility.
• Configure the Energy Management Server to launch an external alarm program to email or page appropriate personnel.

Location

Once ground fault is detected, it is advisable to clear it as soon as possible. Locating a ground fault is a task that can dishearten any electrician and can be a time consuming and frustrating task which may require shutting down some vital equipment and disruption of the power supply.

An alternative non-disruptive method of locating a ground fault within the system is to implement a pulsating ground current concept.

• A parallel grounding resistor is inserted into the circuit via a pulsating relay that operates at a predefined frequency.
• A large probe is than applied around a set of three phase conductors at different power feeders and connected to a suitable DMM
• The feeder that has a ground fault on it, will display a pulsating signal at a predefined frequency, thus narrowing down the ground fault search. (see diagram).

Please contact us with any of your Ground Fault projects. We shall be happy to provide a system that meets your specific needs.