Diffrent voltages in the same raceway.hu

[Capacitorx]

Please forgive me as all I hv rite now to refer to is a old uglys book my 2008 nec was destroyed I'll pick up a 2011 this friday ok the question .i was always under the impression u could run low voltage wit high voltage in the same raceway as long as the low voltage conductor was rated the same as the high voltage conductor.i'm talking 120v with a 24 v .
'.one other question is I always thought making splices in condelets was illegal is this true or false?

 

[infinity]

You cannot run Class 2, 24v power in a raceway with line voltage conductors regardless of the insulation value of the conductors. Look in Article 725. Yes splices are permitted in conduit bodies under certain conditions.

 

[augie47]

As far as mixed voltages, in addition to 300.3 you must also take Art 725 into account. The rules for many lower voltage circuits are covered by Art 725 and those circuits are often prohibited from being mixed with higher voltages.
As far as conduit body splices, it is permissible under restricted conditions, see 314.16


(sorry Rob, stepped on you)

 

[Capacitorx]

Splice in a t

Splice in a t

I won't have a nec to look at until tomorrow after work .the splice is for a combustion ait actuator with an end switch its 24 vac at about 10 va in a reddot 3/4 in. 't' condelet.thanks for your fast response this site rocks.

 

[weressl]

I won't have a nec to look at until tomorrow after work .the splice is for a combustion ait actuator with an end switch its 24 vac at about 10 va in a reddot 3/4 in. 't' condelet.thanks for your fast response this site rocks.

I believe one of the permissive applications is when the low voltage wiring serves the same equipment, like thermostat wiring in the case of HVAC. (I don't have the NEC with me so just shooting from the hip.) Even though it may be permissible, but in certain applications, like both input and output controlled by a PLC, I would not do that for technical reasons, eg. solenoid pulling in may induce a false signal on the limit switch input.

 

[don_resqcapt19]

I believe one of the permissive applications is when the low voltage wiring serves the same equipment, like thermostat wiring in the case of HVAC. (I don't have the NEC with me so just shooting from the hip.) Even though it may be permissible, but in certain applications, like both input and output controlled by a PLC, I would not do that for technical reasons, eg. solenoid pulling in may induce a false signal on the limit switch input.

While "functionally associated" Class 1 control circuit conductors are permitted in with the power conductors, Class 2 and 3 are not.

The typical control circuit of an HVAC system is a Class 2 circuit and is not permitted in the same raceway or cable as the power conductors for the HVAC system.