Safety disconnect switches

Status
Not open for further replies.
C

codequestion

Banned
Location
MD, USA
I have two questions:

1. Is their a standard voltages and amps table for safety disconnect switch fused or non fused? Example 240 VAC 30A or 480VAC 30A etc.
2. Can I use 110VAC disconnect safety switch fused or non fused single pole on 120/208VAC system? Is their such a safety disconnect?
 
codequestion said:
I have two questions:

1. Is their a standard voltages and amps table for safety disconnect switch fused or non fused? Example 240 VAC 30A or 480VAC 30A etc.
2. Can I use 110VAC disconnect safety switch fused or non fused single pole on 120/208VAC system? Is their such a safety disconnect?
Click to expand...

the siemens line seem to be rated 240vac or 600vac in 30/60/100A as common items, and they have higher volt/amp models

any 2pole 240vac disco (blade, lever, handle, fused, non-fused) rated for the amps you need would work, no? you can disco both CCC's with a 2 pole.

[FONT=opensans-regular, Helvetica Neue, Helvetica-, Arial, sans-serif]GE [/FONT]TFN60RCP
Siemens LNF222R
 
Last edited:
UL 98 Enclosed and Dead-Front Switches is the Standard that is used to evaluate safety disconnects.

The Standard requires that the current rating of a general-use switch shall be 30, 60, 100,.... up to 4,000 amps.

The voltage ratings vary from 120 to 600.

Chris
 
codequestion said:
I have 30 amps, 120V, 1 pole circuit. What safety disconnect would work per nec 2014?
Click to expand...

What is the application? Not sure if it needs to be fused or non-fused, but you could use a 2 pole 240 volt 30 amp general duty disconnect switch. Get one with a solid neutral and just use one pole of the switch for the hot leg. Nema 1 for indoor, Nema 3R for outdoor.
 
Jim1959 said:
What is the application? Not sure if it needs to be fused or non-fused, but you could use a 2 pole 240 volt 30 amp general duty disconnect switch. Get one with a solid neutral and just use one pole of the switch for the hot leg. Nema 1 for indoor, Nema 3R for outdoor.
Click to expand...
a 2pole disco, so why not disco both CCC's ??
 
codequestion said:
I would be using outdoor and for hvac equipment. Is their single pole, 60 amps, 120 vac saftey disconnect?
Click to expand...
what exactly is the outdoor hvac equip? why do you keep asking for 120v version, most if not all of it starts at 240vac.
use a blade disco GE TFN60RCP, you can disco both CCC's even though its just one hot leg and one grounded CCC.
$7.50 at HD.
 
I am using hvac on roof for builsing. It is roof top unit. I also have exhaust fan roof which requires 20 amps single pole 120vac and MAU which require 15A 120vac single pole. Any discoonect safety i can use for them?
 
codequestion said:
I am using hvac on roof for builsing. It is roof top unit. I also have exhaust fan roof which requires 20 amps single pole 120vac and MAU which require 15A 120vac single pole. Any discoonect safety i can use for them?
Click to expand...
if it calls for a service disco at the unit, the GE TFN60RCP seems ok to me. many other make/models that will do the job too, i was just giving the ~$8 example.

heck, the Halex version is sub $6 at HD, likely less for you at your supply house.
 
Last edited:
codequestion said:
Can I use 60 amps rated disconnect 120vac and have 15 amps fuse in them?
Click to expand...
if you get a fused disco that accepts a 15A fuse in the fuse size used for that disco, yes, but you still need fuse/ocpd to protect the ckt wires, so why use a fused disco? does the equipmet call for fused disco or fused ckt?

i forget, but does the equip have built-in motor ocpd, if not then i think the disco should be fused properly.

article 430-440 ?
 
ActionDave said:
You can always use a higher rated disconnect than the applied voltage and amperage.

Do you need a fused disconnect?
Click to expand...
Yea for 15amp I need fused disconnect 120V single phase. I was wondering if this is possible for fused disconnect with voltage rating of 120vac and 30 amps current rating.

Sent from my SM-G935U using Tapatalk
 
JFletcher said:
iirc you cannot fuse the neutral; it would pass-thru to the equipment unfused.
Click to expand...
not totally true, you can fuse the grounded CCC in certain circumstances.
lets say fused N is not required, i would still land N on the 2nd pole in disco and use a fuse blank.
240.22
430.36
430.37
 
Status
Not open for further replies.
Top