A Bored Electrician to Answer Your Questions

IAm5toned said:

well different lamps start differently too... mh tends to gradually brighten in intensity while hps will glow dimly for awhile then ignite quite rapidly

man the biggest factor that effects the length of lamp startup is temperature. the higher the ambient temp the quicker the lamp comes on. also the newer the ballast the faster the lamp will ignite. you should see a small glow almost instantly, on either mh or hps. usually with temps in the room temperature range you can expect to have full lamp ignition in no longer than 90secs

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go with a good name brand gfci (such as Pass Seymour Legrand or Leviton) and you cant go wrong

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iloveit said:

I reside in the U.K. & Id like to have my ballast outside of the grow room so the reflector will be connected to a ballast via 10metre cable & the ballast will be connected to a contactor relay timer. My question is will using a 10 metre cable decrease the performance or output of the bulb?

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Tmac123 said:

Great news and bad news....

THe great news is that for one of the units, I was able to open up the top and switch over that wiring connection so that the 120V wire is now on the 'Hot'. I plugged it in, and you were right, it lit right up instantly and then after about 30 seconds grew in intensity pretty fast.

The bad news....the other units I have, when I opened up the top don't have any other wires other than the 277V one that's connected to the 'Hot' atm.

I can see down into the unit housing, and I can see some other wires, but it's kind of difficult to grab them and I don't want to mess anything up inside. Also, these other lights, don't actually have anything written on the outside as far as specs go. They have a label, but everything is blank on them.

Any suggestions for what I should do with these other lights? Assuming I can....

I guess I could somehow change and adapt them to be like the other light so that they will work on a 120V outlet?
Or I could hire an electrician to come in and add a 277V outlet? How much do you think that would run and would you advise it?

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IAm5toned said:

happy for your success on the one...

..however on the others if there is not a wire labled 120 (or 110) theres not much you can do. 277v isnt available in your house panel the highest you can go in a residential setting is 240v hate to be the bearer of bad news.... are the other taps gone altogether or are they just cut real short?

edit- at this stage id wouldnt be shy to cannalbalize a light to see whats going on with it. the other taps maybe cut real short or stuffed up behind the ballast (if there are other taps. you may have a 277v ballast) pictures are helpful theres no moving parts you can mess up in a ballast, there pretty tough. just take care to write down what wire is connected to what...

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Tmac123 said:

Yeah there don't seem to be any wires cut short. just a bunch within the hole that the 3 main wires are coming from. And out of those that I was partially able to pull up, none of them said any other voltage.

I tried to open up the casing for the ballast, but those screws are on pretty tight. Probably torque'd down or something. I'll keep trying and see if I can get in there.

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Infamous313 said:

This is cool man i just found out about you and ive been askin all over about an electrical question. heres the deal im kinda broke right now so i cant afford a vortex fan right now so i picked up 2 of these inductor inline duct fans for like $20 apiece they say theyre 250 boosted cfms so i figure theyre about a good 90cfm constant. i currently only have one of them running as my exhaust in my 4x4x6.5 grow tent with a 400 watt HPS on 12/12, Finally heres the question i was thinking about a dimmer switch for the second fan hooked up to a thermostat inside the tent so the fan would kick on when the temp triggers the tstat. i seen you said dimmers are for incandescents only but is there a way i can wire that 2nd fan just to a thermostat? i was thinking like a manual A/C only t-stat? the fan is only like .4 amps. Thanks bro I appreciate any help.

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IAm5toned said:

the grey wire is the neutral.
the black wire is the hot.
the black wire running from fan#1 to fan#2 is a jumper for the hot wire between the two motors.
the black wire going from fan#2 to the speed control switch is a jumper for the hot wire.
see how the hot wire comes in from the cord, goes to fan#1, then fan#2, then finally the switch.
the brown and white wires on both motors are the speed control legs, ill explain them in a minute

to seperate the two motors for independant operation from the switch do the following, to the letter:

cut the power off, obviously

the black and grey wires that go from fan#1 to the cord, cut them but leave plenty of wire attached to the motor, as much as you can spare.

cut the grey wire on fan#2 leaving as much wire attached to the motor as you can.

the black wire that runs from fan#1 to fan#2, you will need to cut it as close to fan#1 as possible, so all the wire is still attached to fan#2

the black wire that goes from fan#2 to the switch, cut it off close to fan#2 as possible.

cut both the brown and white wires off the switch, leaving most of the wire still attatched to the motor.

set aside the switch

ok now you have the 2 motors isolated.-the grey wire on each motor is a neutral.

the black wires on each motor is the hot.

the brown and white wires are the speed control legs, you will have to use one of them to make the motor work. i cant tell from your diagram which one is high, and which one is low, ill assume for examples sake that the white wire is the high, and thats the speed you want to use.

you will connect the white, the black, and the incoming hot wire from the cord together using a wire nut so that there are three wires twisted together.

you connect the grey wire to the incoming neutral from the cord so that there are 2 wires connected together.

plug it in it should come to life.
unfortunatly you will need two cords to pull this off as you have two motors, and dont forget to capoff or tape up any wires connected to the motors that your not using and i hacked ur image heres what it should look like when ur done

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IAm5toned said:

no, just make sure the wire is at least #14awg with 600v rated insulation

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Infamous313 said:

[Good lookin out dude, ill grab one of those i should be able to hook it up if not ill get back at you. btw do you think i should run those 2 duct booster fans back to back or would they be more effective than putting one at the beggining of my exhaust and the other one at the other end of the exhaust? it's about a ten foot run. or is that more of a hvac question? Either way good lookin out. that one got away on me too.

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Infamous313 said:

[Good lookin out dude, ill grab one of those i should be able to hook it up if not ill get back at you. btw do you think i should run those 2 duct booster fans back to back or would they be more effective than putting one at the beggining of my exhaust and the other one at the other end of the exhaust? it's about a ten foot run. or is that more of a hvac question? Either way good lookin out. that one got away on me too.

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iloveit said:

What does the #14awg ensure?

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whiterino said:

i have a 400watts hps with a coil balast how much power can i save if i use a digital balast instead, or would i even save on power ?

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IAm5toned said:

it ensures the wire itself has enough metal to compensate for the added distance. inside fixtures you often find very small wire, because of a thing known in electrical design as the '6 foot tap rule' . when a wire is less than 6' your allowed 180% of the rated ampacity forthe wire, the reason being that the current has a very short distance to travel, and will not heat up the wire if engineered properly.

when you move the ballast 30' from the fixture that rule goes out the window, voltage drop kicks in, and u lose efficiency of operation. #14 wire compensates for the voltage drop

edit- the 600v rated insulation is critical... your ballasts put out a 600v pulse to start the lamp. using cheaper wire not rated for 600v is taking the chance you will have a short circuit on startup and fry your ballast. its the most important part! frying a 170$ ballast to save 20$ on wire would suck....

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