Disconnect Switches with 5 ungrounded conductors- Separate Disconnects?
Disconnect Switches with 5 ungrounded conductors- Separate Disconnects?
(OP)
We have a piece of equipment with 480V 3phase (no neutral) and 240 L1/L2 running into it for a total of 5 wires. Isn't there some rule that you have to break all 5 ungrounded conductors with one disconnection switch, instead of having one switch for the 240V and another switch for the 480V? Seems to me it should be common sense....





RE: Disconnect Switches with 5 ungrounded conductors- Separate Disconnects?
Usually see this as the case 480vac disconnect, not a disconnect with 5 wires which is special.
RE: Disconnect Switches with 5 ungrounded conductors- Separate Disconnects?
RE: Disconnect Switches with 5 ungrounded conductors- Separate Disconnects?
When we build UL panels, we're just required to label them thus:
55.4 An industrial control panel intended to be provided with more than one supply source such that more
than one disconnect switch is required to disconnect all power within the control panel shall be marked
with the word ²CAUTION² and the following or equivalent: ²Risk of Electric Shock – More than one
disconnect switch may be required to de-energize the equipment before servicing.²
Best to you,
Goober Dave
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RE: Disconnect Switches with 5 ungrounded conductors- Separate Disconnects?
Keith Cress
kcress - http://www.flaminsystems.com
RE: Disconnect Switches with 5 ungrounded conductors- Separate Disconnects?
"Will work for (the memory of) salami"
RE: Disconnect Switches with 5 ungrounded conductors- Separate Disconnects?
I found another solution while I was away--- alot of companies make linkages that can join two 2pole or 3pole switches. 5p and 5p switches exist but are rare.
RE: Disconnect Switches with 5 ungrounded conductors- Separate Disconnects?
Here's an example: Eaton 6-Pole Safety Switch
I agree that a single switch makes a safer product, but it's not a requirement.
Best to you,
Goober Dave
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