voltage drop for high bay lights

[ramsy]

Ramsy, I take it you have never worked with lighting control systems?

Are you picking on me?

Using Class 2 wiring for control is very common. Not sure why you are so against it.

Whats wrong with using some J-Box & switch leg, if its already there, to control a relay without T-Stat wiring?

 

[curt swartz]

Are you picking on me?

Whats wrong with using some J-Box & switch leg, if its already there, to control a relay without T-Stat wiring?

Not trying to pick on you!

Just questioning why you are so against using CL2 wiring for lighting control when its very common. Even may years ago, before energy codes existed CL2 wiring was common for commercial and residential switching. Member Gar has GE RR relays in his house.

 

[ramsy]

neither the spool or wire says voltage. Wire: Vericom E364604-T 18 AWG 4 cond 60 C (UL) Type CL2R CMR (UL) C (UL) Sunlight resist.

Found your cable with 150 volt insulation, but with some exceptions in 725.136, a minimum of 600 volt insulation is required to combine with system voltage raceways.

 

[ramsy]

Just questioning why you are so against using CL2 wiring for lighting control

My enthusiastic preference for using system raceways were available, may be influenced by competitive practices in my sector.

In residential service we find some existing homes were built with lighting relay systems in the attic.

Compatible replacements for defective panel switches, power supplies, transducer, and relays are often special order, with shipping, that contractors will bid for same price as remodel wiring.

Contractors don't hire monkeys with skills or patients to troubleshoot these relay systems in hot attic spaces, most just upsell the remodel wiring, the same way panel flippers upsell 200 amp service upgrade when the old fuse box gets dusty.

 

[curt swartz]

My enthusiastic preference for using system raceways were available, may be influenced by competitive practices in my sector.

In residential service we find some existing homes were built with lighting relay systems in the attic.

Compatible replacements for defective panel switches, power supplies, transducer, and relays are often special order, with shipping, that contractors will bid for same price as remodel wiring.

Contractors don't hire monkeys with skills or patients to troubleshoot these relay systems in hot attic spaces, most just upsell the remodel wiring, the same way panel flippers upsell 200 amp service upgrade when the old fuse box gets dusty.

The OP was planning to run new MC for the switching so there was not an existing raceway or wiring in place.

If there was existing wiring and voltage drop was the only concern the same relay could be used. You would connect the low voltage control wires together and then switch the black power supply lead on the relay.

 

[ramsy]

The OP was planning to run new MC for the switching so there was not an existing raceway or wiring in place.

Long runs of T-stat wiring switch legs is certainly less costly than raceways, I see your point, and will consider it from now on.

If ever bidding new work may also show switch-rated circuit breakers, without switch legs.

 

[hbiss]

Found your cable with 150 volt insulation, but with some exceptions in 725.136, a minimum of 600 volt insulation is required to combine with system voltage raceways.

As I said, all CL2 and CL3 cable has 150V insulation. It's not allowed to be stated on the jacket or spool label because it might be used for that voltage. CL2 and CL3 is supposed to only be used with listed CL2 and CL3 power sources which are well below 150V.

The insulation rating is listed in the cable specs for engineering purposes or if not used per the NEC.

-Hal

 

[Stevenfyeager]

Was I worrying about nothing - having low v wires in the same switch box as 120 v ?
The NEC® (National Electric Code) allows line-voltage wiring devices, e.g., light switches, dimmers, and receptacles to be placed in the same multi-gang box as low-voltage wiring devices, e.g., cable jacks and phone jacks

 

[Stevenfyeager]

Another situation similar: inside emergency exit sign powering up a battery outside emergency light. The prints show each exit door having an inside exit sign/light connected to an outside battery powered emergency light. What wire do you usually use between the two ?