Dimmer 0-10v

Status
Not open for further replies.
Jason Spray said:
If you already have the Power for the fixture taken care of, and you are just needing to take care of the 0-10v wiring, you CAN use MC cable, it's just overkill. You could use 2/18 cable.
Click to expand...

Don't you have to run a switched hot from 0-10v dimmer no matter what?
 
mstrlucky74 said:
Don't you have to run a switched hot from 0-10v dimmer no matter what?
Click to expand...

Not if the dimming device has a near zero power mode at one end of its control range.
If the driver implements a minimum light level regardless of the control voltage, then yes, some sort of switched power is required.
 
mstrlucky74 said:
:?:dunce:
Click to expand...

Restated:
If the combination of the dimmer control and the dimming driver/ballast can turn the light source off completely, then you need no switched feed.
If it can only dim it to a preset minimum level, then you need a switched hot too.
RF remote controls typically have a totally off function. Not sure whether 0-10 controls can do that too.
 
GoldDigger said:
Restated:
If the combination of the dimmer control and the dimming driver/ballast can turn the light source off completely, then you need no switched feed.
If it can only dim it to a preset minimum level, then you need a switched hot too.
RF remote controls typically have a totally off function. Not sure whether 0-10 controls can do that too.
Click to expand...

0-10's need a switchleg, or they glow softly, forever. :weeping:
digital controls can have the light fed unswitched.
 
Fulthrotl said:
0-10's need a switchleg, or they glow softly, forever. :weeping:
digital controls can have the light fed unswitched.
Click to expand...

Thanks. So my question is if you need two control wires and one switch leg ran from the 0-10v dimmer can you run 12/3 600v MC or you need the MC-PCS?
 
No. See 725.136(I)(1)

(1) Either (a) all of the electric light, power, Class 1, non–
power-limited fire alarm and medium-power networkpowered
broadband communications circuit conductors
or (b) all of the Class 2 and Class 3 circuit conductors
are in a raceway or in metal-sheathed, metal-clad, non–
metallic-sheathed, or Type UF cables.
Click to expand...

Either the line voltage has to be in a separate cable with the 0-10v conductors run outside of it or the 0-10v conductors have to be in a separate cable and then they can be run with the line voltage conductors under a common sheath or armor. This is what the luminary cable is.

So to answer your question yes, you have to use either MC-PCS or separate cable runs.

-Hal
 
hbiss said:
No. See 725.136(I)(1)



Either the line voltage has to be in a separate cable with the 0-10v conductors run outside of it or the 0-10v conductors have to be in a separate cable and then they can be run with the line voltage conductors under a common sheath or armor. This is what the luminary cable is.

So to answer your question yes, you have to use either MC-PCS or separate cable runs.

-Hal
Click to expand...

Sorry to beat a dead horse. I completely understand what your saying. So whether your circuit is brought to the switch or to a box up by the lights you will need a switch leg run from the switch, correct? Thanks
 
mstrlucky74 said:
Sorry to beat a dead horse. I completely understand what your saying. So whether your circuit is brought to the switch or to a box up by the lights you will need a switch leg run from the switch, correct? Thanks
Click to expand...

You need a hot, neutral and the 0-10v control pair from the fixture to the dimmer.

What would you do if conduit was required? Just curious.
Click to expand...

Only way I could think of would be two separate runs- one for the line voltage and one for the low voltage.

But then I'm thinking, what about 18/2 tray cable in one conduit with the line voltage?

-Hal
 
I'll ask what I hope is a dumb question that I've always wondered about.

I see there being two kinds of "low voltage:" VDV (Voice, Data, Video) and just plain, you know, low voltage like a thermostat that I deal with everyday. Does this 0-10 V dimmer actually transmit data or is it just low voltage control circuitry?

If the latter, does it NEED separation, or is it just because it's required? Because just plain low voltage isn't susceptible to interference, is it?
 
The 0-10v is CL2, varying voltage, no data. Does it technically need separation to operate, no. It's because the NEC requires it in this instance and any other where CL3 or CL2 conductors need to run with line voltage.

-Hal
 
Last edited:
hbiss said:
The 0-10v is CL2, varying voltage, no data. Does it technically need separation to operate, no. It's because the NEC requires it in this instance and any other where CL3 or CL2 conductors need to run with line voltage.

-Hal
Click to expand...

So are you saying if you have a conduit stub or piece of Greenfield you can combine the 600v switch leg along with the Class 2 control wires?
 
MAC702 said:
I'll ask what I hope is a dumb question that I've always wondered about.

I see there being two kinds of "low voltage:" VDV (Voice, Data, Video) and just plain, you know, low voltage like a thermostat that I deal with everyday. Does this 0-10 V dimmer actually transmit data or is it just low voltage control circuitry?

If the latter, does it NEED separation, or is it just because it's required? Because just plain low voltage isn't susceptible to interference, is it?
Click to expand...

Actually, per manufacturers, in this case specifically Cooper, Hbliss is wrong when you have long distances, If you have over 400 feet of 0-10V it is recommended that it be run separately or you may get interference that affects the quality of the dimming.
 
mstrlucky74 said:
So are you saying if you have a conduit stub or piece of Greenfield you can combine the 600v switch leg along with the Class 2 control wires?
Click to expand...

What he said, was that you could not because the code doesn't allow it. That is the "period" of it. IF the wire is rated for 600 volts and you reclassify the wiring method as class one, THEN they can be combined.
 
Strathead said:
What he said, was that you could not because the code doesn't allow it. That is the "period" of it. IF the wire is rated for 600 volts and you reclassify the wiring method as class one, THEN they can be combined.
Click to expand...

No you cannot! Go back and read 725.136(I)(1). If it was as easy as you say you could use 4-wire MC and if that were the case why do you think wire manufacturers went through the trouble to produce luminary cable MC?

-Hal
 
Last edited:
Strathead said:
Explain to me how you connect separate the 0-10v from the line voltage wires on the junction box end. I am not an expert by any stretch. I actually wasn't aware Southwire made this statement, however I just read article 725.136 and I don't see where this is allowed, under any circumstance with power and lighting wiring and it is very limited with Class 1 wiring. I am respectfully waiting to be informed in regards to the code, not some claim by Southwire.
Click to expand...

When I started the project, I was going to use 12/4 MC. I picked up the 2008 NEC and could not find any section that allowed it. Then I heard about "Luminairy MC". I applied Art 725.136(D)(1). Therefore, I maintained at least 1/4" separation between Class 1 and Class 2 conductors in my enclosure. Respectfully submitted.

hbiss said:
No you cannot! Go back and read 725.136(I)(1). If it was as easy as you say you could use 4-wire MC and if that were the case why do you think wire manufacturers went through the trouble to produce luminary cable MC?

-Hal
Click to expand...

Thank you Hal. You said it much better than me.
 
There is no data control over the 0-10v control lines, in fact you can use a simple variable resistor (potentiometer) with many of the new drivers. It will not provide local control but can be used to set a light level other than full blast. I have had good luck with 100k linear pots.
 
Status
Not open for further replies.
Top