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Grounding the secondary of a small transformer

Grounding the secondary of a small transformer

Grounding the secondary of a small transformer

(OP)
We have a small 230V device placed in a metal housing.
We are going to display in an exibithion in US and in order not to modify it for 110V, we decided to use a 400VA 110V/230V transformer.
Is it nessecary to ground the secondary of the transformer for safety reasons?

RE: Grounding the secondary of a small transformer

Excerpt from the Canadian code. The US code is similar.
10-106 Alternating-current systems (see Appendix B)
(1) Except as otherwise provided for in this Code, alternating-current systems shall be grounded if
(a) by so doing, their maximum voltage-to-ground does not exceed 150 V; or
(b) the system incorporates a neutral conductor.
(2) Wiring systems supplied by an ungrounded supply shall be equipped with a suitable ground fault detection
device to indicate the presence of a ground fault.
We would use a 120:120/240 transformer.
That is; One with a 120 Volt primary and two 120 Volt secondaries which may be connected in series for 240 Volts.
An equally valid option is to use a transformer with a center tapped 240 Volt secondary winding.
Ground the center point.
The maximum voltage to ground will be 120 Volts and you will not need a ground fault detection device.

Bill
--------------------
"Why not the best?"
Jimmy Carter

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