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T rating of a switch #220790 05/10/20 03:22 PM
Joined: Apr 2013
Posts: 4
R
Rob2019 Offline OP
New Member
1) What does it mean by *T rating of a switch*?

2) Where can I find more info on different types of general purpose switches?

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Re: T rating of a switch [Re: Rob2019] #220796 05/15/20 05:44 PM
Joined: Aug 2011
Posts: 19
G
grich Offline
Member
T means the switch is rated for switching tungsten lamp loads...the switch contacts can handle the momentary inrush current that the cold filaments will draw.

Re: T rating of a switch [Re: Rob2019] #220798 05/16/20 01:27 AM
Joined: Jul 2002
Posts: 8,329
Trumpy Offline
Member
Rob,
Welcome to ECN,
What sort of a switch is this and what sort of application is this being used in?
I suspect that the T rating, as you refer to is the Thermal Current rating.
Switches, if they are going to be used to interrupt/make inductive loads depend heavily on "AC Ratings", like AC-3 or the like, otherwise the switch contacts will be seriously damaged by the arc created when the contacts open or close.

Re: T rating of a switch [Re: Trumpy] #220807 05/16/20 10:52 PM
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Posts: 4
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Rob2019 Offline OP
New Member
Got the reply from another member; Grich

T-switches means the switch is rated for switching tungsten lamp loads....the switch contacts can handle the momentary inrush current that the cold filaments will draw.

Re: T rating of a switch [Re: Rob2019] #220810 05/17/20 03:13 PM
Joined: Dec 2002
Posts: 204
G
geoff in UK Offline
Member
Interesting but confusing. I'll admit I hadn't heard of T rating and was waiting for an informed answer.
However, I've always thought inductive loads much more demanding of switches, so is T rating a "plus", or more a limitation?


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