Isolation provides peace of mind

The MultiRail, like all current transformer (CT) operated meters supplied by Northern Design, has fully isolated current inputs.

The MultiRail, like all current transformer (CT) operated meters supplied by Northern Design, has fully isolated current inputs.

Although adding to the cost of manufacture, Northern Design considers that safety should not be compromised just to reduce cost.

Although full isolation is not essential for compliance with the present requirements of BS EN61010-1, there are certain fault conditions under which the voltage on unisolated current inputs, namely the CT secondaries, can rise to dangerous levels.

Internal isolating transformers in Northern Design's MultiRail provide complete galvanic isolation for the current inputs.

Apart from safety, this allows the secondaries to be earthed and gives the user complete flexibility in how he connects the CTs - individually, star or delta connected.

Also, if the CTs are shared with other instruments, their performance will not be affected if a MultiRail is added into the circuit.

Isolation also allows the meters to be used directly connected under the correct conditions.

Back to top