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The Great Debate 120/240

wspcolorado

Member
I have a 240 line and 30 amp 120 line comming into the laundry room. We need to be able to use the laundry when the lights are not running.

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Im using Lumatec 120/240 ballast and have both sets of plugs.

I plan on running:
2 - 1000 Watt Lumatec Ballast
1 - Vortex
1 - Air4
1 - Co2 Regulator
1 - Small Registerbooster fan
possibly a Phason

Any suggestions on how the best way to hook the electrical? Ideally I would love to have the lights on the 240 and everything else on the 120
 

PharmaCan

Active member
Veteran
Just for starters, you don't have a 30 amp 120v circuit. You may have a 30 amp breaker hooked to the circuit, but that wire is either #12 or #14, which means you have either a 20 amp or 15 amp circuit. If you have a 30 amp breaker on that line, you need to change it to 15 or 20 amps.

If I was going to modify your wiring I think I would use that existing 240v, 2 gang box as a junction box and run one set of lines for your dryer and one set for your lights - that is, you would have two 240v receptacle boxes instead of the one you have now. This wouldn't increase the capacity of your circuit; it would simply give you more places to plug stuff into. The two boxes couldn't be used at the same time. If I was doing the job for someone who was really, really stupid, I'd wire it so that only one of the 240v receptacles/boxes would work at a time. If you are pretty sure that no one will use the dryer during lights on, such a precaution would be unnecessary and it's a pretty simple job.

PC
 

TacoSusio

Member
If I was doing the job for someone who was really, really stupid, I'd wire it so that only one of the 240v receptacles/boxes would work at a time. If you are pretty sure that no one will use the dryer during lights on, such a precaution would be unnecessary and it's a pretty simple job.

PC

How exactly would you do that, Pharma?
 

Lazyman

Overkill is under-rated.
Veteran
Just for starters, you don't have a 30 amp 120v circuit. You may have a 30 amp breaker hooked to the circuit, but that wire is either #12 or #14, which means you have either a 20 amp or 15 amp circuit. If you have a 30 amp breaker on that line, you need to change it to 15 or 20 amps.

If I was going to modify your wiring I think I would use that existing 240v, 2 gang box as a junction box and run one set of lines for your dryer and one set for your lights - that is, you would have two 240v receptacle boxes instead of the one you have now. This wouldn't increase the capacity of your circuit; it would simply give you more places to plug stuff into. The two boxes couldn't be used at the same time. If I was doing the job for someone who was really, really stupid, I'd wire it so that only one of the 240v receptacles/boxes would work at a time. If you are pretty sure that no one will use the dryer during lights on, such a precaution would be unnecessary and it's a pretty simple job.

PC

:yeahthats
 

DarkLance

Member
edit2:having a 30amp breaker installed there is pretty much asking for a fire

edit1: one more thing, grow-room in the laundry? Get a GFCI breaker and learn how to wire it properly (at a minimum a GFCI receptacle). Also might consider an AFCI on the main box
 

PharmaCan

Active member
Veteran
How exactly would you do that, Pharma?

Using a double pole three position switch would work, although it would require manual operation which could lead to problems if you forgot to flip the switch after using the dryer. To make it automatic you could use two timers so that each was set to turn either receptacle on for a certain time period each day. They might even make one timer that would do the same thing, I don't know.

I believe OP would like to know about Power Factor, etc concerning 240V equipment. Or at least, that is a question I have and would like to see answered here.

There is so much info about this available on this forum, it's easier for someone to do a search than it is to re-type it - for me anyway.

Also, wspcolorado, white romex normally means #14. 15 AMP!

No it doesn't. All Romex used to be white. Looking at the vintage of the plumbing in that wall, I'd make an educated guess that the wiring was installed before yellow Romex ever existed.
under no circumstances should you run more than 1800 watts continuously on that circuit

Again, not true. You should not exceed 80% of the circuit's rating for a continuous load, which would give you 1,440 maximum allowable watts on a 15 amp circuit.
having a 30amp breaker installed there is pretty much asking for a fire

In all fairness, this one you did get right.

PC
 

madpenguin

Member
No it doesn't. All Romex used to be white. Looking at the vintage of the plumbing in that wall, I'd make an educated guess that the wiring was installed before yellow Romex ever existed.

PC

PC is probably right on this one. Only it was the black dryer cable that tipped me off.... ;) (it should be orange if #10 after color coding took effect).

If that is indeed #10 AWG cable feeding that dryer receptacle, then that white wire is almost certainly #12 AWG. This is why cable has markings on the outside. When in doubt, read the outer sheathing..... If it is #12 and there really is a 30A breaker on that line, you need to swap it out for a 20A breaker ASAP.
 

cocktail frank

Ubiquitous
Mentor
ICMag Donor
Veteran
i'd say romex starting getting rainbow colored w/in the last 10 years.
not sure exactly when, but i know it was either white or black when i started this profession.

pharma hit it all right on the head, i have nothing more to add here.
 

wspcolorado

Member
ended up using the 240 line, unplugging when we need to do laundry. Any suggestions on how to remind my girlfriend to plug the lights back in DOH!!!!!!!!
 
E

Eminem

ended up using the 240 line, unplugging when we need to do laundry. Any suggestions on how to remind my girlfriend to plug the lights back in DOH!!!!!!!!


Slap her, and tell her it only gets worse next time?

Nah just kidding.

A note on the dryer door?

No weed for her?


I am thinking a digital timer and a DPDT contactor. The timer would be set for 12/12 and would allow only one circuit to be active at a time. If you are comfortable with wiring, this would be easy to wire up.


How are you running your 12/12 lights? The reason I ask is because if that 240 line is running your timer like a hot water heater timer, you are shutting down the clock and messing with the light schedule when you unplug it.
 

wspcolorado

Member
Pharma, - funny. may just work!!

Eminem, - I think no weed just may do the trick, we ended up doing the DYI 4 light controler, its turned on and off by the 120 plug.
 
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