DARKROOM - Electric Questions

[Salmo22]

As we emerge from COVID restrictions and I recover from a recent surgery, completion of my humble home darkroom can again become a high priority.

I'm expanding an existing, and underutilized, pantry to serve as my home darkroom. While the pantry currently has two switched can lights in the ceiling, there are no electrical outlets. A few feet away is a 220v outlet in my garage that was originally intended to allow using a welder. It is on it's own dedicated 200v circuit with breaker. My thought is to keep the existing switched can lights and feed all other electrical needs by converting the dedicated 220v circuit to 120v.

My questions are as follows;

1. Will normal 20 Amp 125-Volt Duplex GFCI outlets work for my enlarger and related darkroom uses?

2. Should I consider adding surge protection or a stabilizing power supply?

3. In the future, will changing my enlarger head from the Dichro 45S colorhead to a cold light LED source (i.e Heiland) create any issues that I should be planning for now?

To help with your answers, I've acquired and intend to install a wall-mounted Beseler 45V-XL with the Dichro 45S colorhead and GraLab 451 solid state digital timer. In addition to the enlarger arrangement, I'll have two or three old school GraLab 300 timers, a Jobo CPP2, Thomas Safelight, print inspection light, etc. I've attached a copy of my floor plan for reference.

Your wise counsel and suggestions are appreciated.

[Tin Can]

Should be fine

I prefer a breaker box GFCI and grounds to all metal

The Heiland should draw enough power to run old timers

I have had trouble with DIY light load LED and old timers

[Eric Woodbury]

You can split your 220Vac circuit into two 110Vac circuits with a common return. This is legal. I wouldn't bother with extras such as surge or OV or other protections. Nor stabilization. I'm using an LED source now and it works fine on regular old juice. My darkroom doesn't take much power except for a space heater and small water heater. All my lights are LED. Stereo doesn't take much. Mostly, it is a matter of having lots of outlets. If I were you, I'd get some nice switched multi-outlet power busses. And depending on your white lighting requirements, consider using track lighting.

Be safe and keep one hand in your pocket.

-ejw-

[John Layton]

Assuming that you are the only person using your darkroom...you can split that 220 circuit into two 120's...and dedicate one of those to just your enlarger bench. In other words...no other uses for that circuit. Then, the remaining 120 can be dedicated to everything else in the darkroom, helping to ensure minimal interference with line voltage on your enlarger circuit...which is very important!

Do be careful that various devices which employ heating elements (film dryers, dry mounting presses, electric room heaters), should all be isolated from your enlarger circuit!

I also happen to own a Heiland VC LED head for my Zone VI enlarger...and so far its been extremely consistent in output, without the employment of any additional voltage stabilization scenario, excepting the aforementioned enlarger circuit isolation. I do have a voltage stabilizer for my Beseler 4x5 enlarger...but really don't use that enlarger all that much since the acquisition of my Zone VI.

And yes...normal 125 volt gfci's will be fine for your darkroom, and, if below grade (typical for a home basement) likely required by your local electrical code. The only exception would be if you were using electric motors with high starting torques (like a large diameter chop saw) - which can throw a gfci on those occasions when other outlets in that circuit are also in current (ha!) use. Not a likely scenario in your darkroom.

[jp]

A normal 20a circuit with GFCI should be fine.

One thing you might consider is using track lights instead of cans. I have a tracklight for red safelight LEDs. Then I can point them where I want them. Use separate light switches.. One for normal light, one for safelights. Sometime I'll have a tracklight for normal lighting in the darkroom, but that's less useful than the safelights.

Another thing I did was (with relays) lock out (disconnect) the main light when the safelight is on. You could probably do it with a 3-way switch on the safelight and daisy chain the normal main light switch behind that.

The welder circuit might/might not have a neutral. If it's just two hots and ground (like a hot water heater), it's not suited for your repurposing. If it has two hots, a neutral, and a ground, it's good. Either change the breakers it connects to in the main box to 20a duplex or have a subpanel where the welder outlet is located.

[Tin Can]

I have 2 cheap 5 button remotes, not wifi, tiny battery lasting 5 years so far, they switch 4 circuits
One is mounted outside the DR door, just in case I misplace the primary

2 safe lights, one fan and big overhead all bounce off the ceiling so I never need to climb a ladder again

Since I process film in tanks with lids, I can safely switch anything, as needed

[Greg]

Present darkroom is my 4th. Measures 8' x 17' which was determined by a pre-existing wall.
Two 20 amp circuits both on GFIs: Was an overcall in retrospect. Two 15 amp circuits would have been more than I needed. Plus had to use 12 gauge wire. With 15 mp circuits I could have used 14 gauge wire which would have been a lot easier to work with.
I installed 2 water valves to shut off the water supply to the darkroom when I wasn't using the darkroom - good idea. Thought to do the same for the two electrical circuits - bad idea... At different times of the year I run either a humidifier or a dehumidifier in the darkroom. I shut off the power to the darkroom several times forgetting that I had also shut off the power to the humidifier or the dehumidifier. Removed the switched and capped the 4x4 box with a plate.
16 total outlets: Good pre planning of where to place them but I have racks of print drying screens located under the sink and forgot to place an outlet behind them to wire up 2 computer fans (also would have included a wall switch for them) which would have greatly decreased my FB print drying times.
One 2'x4' and one 2'x2' recessed fluorescent lighting fixtures: replaced them with LED fixtures which greatly increased the amount of light.
Use an ARISTA high intensity UV light box on a timer. Very rarely it pops the GFI. Have yet to figure out why. An electrician told me this happens sometime with very sensitive GFIs. Should have planned better for the print inspection light's location gut not worth changing.
Thomas Sodium Vapor safelight which I have had to lower its light output.
Built in a red safelight in a wall on one side of the sink which I have yet to use.
Print timers and power supply are located on a shelf above the dry side's counter: Allowed me to totally free up the counter space. Great when loading ULF film holders.
Densitometer located in my "work" space: No heed to be located in the darkroom.
Radio and CD player located high on shelves. Had to run it and more off a wall mounted hidden outlet strip. Hadn't planned on this but worked out better than if I had included one more wall outlet.

Ass I had always told my students: "Mistakes are teachers in disguise"

[Drew Wiley]

All depends on if you might hypothetically scale up to higher voltage or higher wattage equipment further down the line, especially if you contemplate something like 8x10 color enlarging. It's easier to bring in 240 voltage early on, rather than retrofit. But 20A 115 is ample for what you currently have in mind. I'm personally nitpicky about getting good quality CFCI outlets and breakers from reputable electrical supply houses, and not from the usual Cheapo Depot type suspects - it really can make a huge difference in reliability. Likewise lighting. But any kind of wattage glutton like routine air conditioning will be way less expensive if run on a dedicated 240 V circuit.

[maltfalc]

move the safelight and fan switches away from the other switches, you don't want to mix those up.

[domaz]

I'm not clear on what you mean with respect to the 220v outlet and converting it to 120v. Ya you could split it to two 120 breakers, but if that outlet was for a 50 amp welder circuits that would mean your feed wires would be huge 6 gauge cable. Best thing to do is either leave the 220v alone and put in new additional breakers with dedicated new romex runs, or take out the 220 breaker and outlet and use the existing wire to pull new romex through. 6 gauge wire is hard to work with, is not something you need and mixing cable sizes on a circuit is bad practice.

Side note- the 220v outlet in a garage would be really useful for an Electric Vehicle charger if you ever intend to upgrade your car.

[Salmo22]

Great comments all, please keep them coming. I forgot to mention that HAVC is already serving this pantry space will sized fine for the small expansion. I also will be installing two exhaust fans over the custom sink.

[Salmo22]

I'm not clear on what you mean with respect to the 220v outlet and converting it to 120v. Ya you could split it to two 120 breakers, but if that outlet was for a 50 amp welder circuits that would mean your feed wires would be huge 6 gauge cable. Best thing to do is either leave the 220v alone and put in new additional breakers with dedicated new romex runs, or take out the 220 breaker and outlet and use the existing wire to pull new romex through. 6 gauge wire is hard to work with, is not something you need and mixing cable sizes on a circuit is bad practice.

Side note- the 220v outlet in a garage would be really useful for an Electric Vehicle charger if you ever intend to upgrade your car.

I built and wired this house 38 years ago. I did all the 20 amp circuits with 2/12/ground. It is a pain to make up the boxes and trim out, but I like big copper.

Unfortunately, the 220v has a 50 amp breaker and is 6 gauge copper. Like the rest of the house, I pulled that one homerun myself. What I'm hoping to avoid is extending existing circuits and create possible problems with overload. Thus, I was hoping to pirate the 220 as is service nothing but that single welder outlet. It has been nearly four decades since I wired this house, so I'm open to ideas.

[Salmo22]

move the safelight and fan switches away from the other switches, you don't want to mix those up.

Terrific suggestion - thanks.

[Salmo22]

All depends on if you might hypothetically scale up to higher voltage or higher wattage equipment further down the line, especially if you contemplate something like 8x10 color enlarging. It's easier to bring in 240 voltage early on, rather than retrofit. But 20A 115 is ample for what you currently have in mind. I'm personally nitpicky about getting good quality CFCI outlets and breakers from reputable electrical supply houses, and not from the usual Cheapo Depot type suspects - it really can make a huge difference in reliability. Likewise lighting. But any kind of wattage glutton like routine air conditioning will be way less expensive if run on a dedicated 240 V circuit.

4x5 black and white printing is as big as I'll get. No color for me. So the Beseler 45V-XL will likely outlast me. As I noted, it is possible I'll convert to a cold light LED source somewhere down the road, but that doesn't seem to be an issue. What brand of CFCI outlets and breakers to your recommend?

[Salmo22]

If any of you would be willing to share photos of your darkrooms with me, I'd be most appreciative. PM me if you'd rather not post here and I'll get you my email address.

[Salmo22]

Assuming that you are the only person using your darkroom...you can split that 220 circuit into two 120's...and dedicate one of those to just your enlarger bench. In other words...no other uses for that circuit. Then, the remaining 120 can be dedicated to everything else in the darkroom, helping to ensure minimal interference with line voltage on your enlarger circuit...which is very important!

Do be careful that various devices which employ heating elements (film dryers, dry mounting presses, electric room heaters), should all be isolated from your enlarger circuit!

I also happen to own a Heiland VC LED head for my Zone VI enlarger...and so far its been extremely consistent in output, without the employment of any additional voltage stabilization scenario, excepting the aforementioned enlarger circuit isolation. I do have a voltage stabilizer for my Beseler 4x5 enlarger...but really don't use that enlarger all that much since the acquisition of my Zone VI.

And yes...normal 125 volt gfci's will be fine for your darkroom, and, if below grade (typical for a home basement) likely required by your local electrical code. The only exception would be if you were using electric motors with high starting torques (like a large diameter chop saw) - which can throw a gfci on those occasions when other outlets in that circuit are also in current (ha!) use. Not a likely scenario in your darkroom.

Having one of the new 120 circuits dedicated to my enlarger bench is a terrific idea.

[Eric Woodbury]

I can send some photos later.

Take your 50A circuit and put a subpanel there. Maybe a 4 position or 6 position box. Then with surface plastic conduit, make everything just right.

My DR has 4, 20A breakers. 1 for heat/AC, 1 for all the lighting, 1 for all the non-lighting, and 1 for general stuff. Then I have outlets up high for safelights. Track lighting has a pull-string switch. If I want to load film, then I OFF the lighting circuit. If I need the heater or AC on, I flip that switch. Outlet cover plates are color coded so I know which outlet goes to which switch. Oh, I don't use the breaker for switches. The subpanel is in another room as it services many other things in the building. But those four circuits come to GFI outlets and then 3 of them to normal 20A wall switches. The general stuff circuit, doesn't have a switch.
It is the stereo, film fridge, clock, ... that kind of stuff.

GFI breakers are expensive and if you get a leak in your circuit, it can be very difficult to trace.

When I leave the darkroom, I OFF all the switches. I've known too many photogs that have had electrical fires in their DR. How many is too many -- more than zero. Two actually.

Hope this makes a little sense.

[Salmo22]

I can send some photos later.

Take your 50A circuit and put a subpanel there. Maybe a 4 position or 6 position box. Then with surface plastic conduit, make everything just right.

My DR has 4, 20A breakers. 1 for heat/AC, 1 for all the lighting, 1 for all the non-lighting, and 1 for general stuff. Then I have outlets up high for safelights. Track lighting has a pull-string switch. If I want to load film, then I OFF the lighting circuit. If I need the heater or AC on, I flip that switch. Outlet cover plates are color coded so I know which outlet goes to which switch. Oh, I don't use the breaker for switches. The subpanel is in another room as it services many other things in the building. But those four circuits come to GFI outlets and then 3 of them to normal 20A wall switches. The general stuff circuit, doesn't have a switch.
It is the stereo, film fridge, clock, ... that kind of stuff.

GFI breakers are expensive and if you get a leak in your circuit, it can be very difficult to trace.

When I leave the darkroom, I OFF all the switches. I've known too many photogs that have had electrical fires in their DR. How many is too many -- more than zero. Two actually.

Hope this makes a little sense.

Thanks Eric for your suggestions. I like the idea of a 4 position subpanel box.

[martiansea]

Are GFCIs really necessary for the wall with the enlarger? Those are intended for ground faults caused by an appliance falling in water. They're required for outlets near water, but otherwise unnecessary. Have them by the sink of course, but just there. I think the enlarger would be happier without it.
I would upgrade the enlarger to some kind of LED light source right away, before even setting it up to use. No point in fooling with the old technology anymore. Do everything possible to minimize the energy required to run everything. Make it so the heater in the Jobo is the neediest thing. Since you're building the room up new, this is the attitude I would take.

[Eric Woodbury]

GFIs are cheap and provide great protection. Required most everywhere there is exposed ground, earth ground, bare slabs, metal pipes. All damp locations, garages at or below grade, etc. Also within 4' of a door that leads immediately to outside (so that when you're outside and need some power, you don't open the door and get unprotected power).

You are allowed to put a GFI on an old two wire circuit for remodels (no earth or U-ground previously available). This is an easy way to get that third hole in homes that have older wiring. Also, altho you can cascade GFIs, this leads to confusion when there is a fault, so best not to do so.

Your enlarger nor any other piece of equipment won't know the GFI is in place. GFI work on the idea of balanced current. The feed and return wires go through a toroid such that the current to the load vs the current on return can be monitored with the magnetic field. Cute trick. The toroid is not in the circuit to the load.

"Old technology" ... that's what darkrooms are. LED light sources are a lot of fun and very efficient with power, but a cold light is very efficient with power too. Neither are ON very much, so the total output energy is low.

[Salmo22]

Are GFCIs really necessary for the wall with the enlarger? Those are intended for ground faults caused by an appliance falling in water. They're required for outlets near water, but otherwise unnecessary. Have them by the sink of course, but just there. I think the enlarger would be happier without it.
I would upgrade the enlarger to some kind of LED light source right away, before even setting it up to use. No point in fooling with the old technology anymore. Do everything possible to minimize the energy required to run everything. Make it so the heater in the Jobo is the neediest thing. Since you're building the room up new, this is the attitude I would take.

An interesting approach. Thank you.

[Paul Ron]

as for gfi?... check your local electrical codes first! my bathroom and darkroom are fully protected... why take a chance over saving a few bucks?

[Jim Jones]

Salmo22: My last darkroom was smaller than yours, but had over 20 outlets. Sometimes most had something plugged into them, ready to use. The outlets and lights were all on one 20 amp GFCI breaker in the fuse box. It would have been better planning to have two independent circuits in the darkroom, but not doing so never caused any problems. The darkroom before that one had a separate 30 amp circuit for an air conditioner and possible future use. I agree that installing 20 amp wiring once is much better than updating to it later. Semi-permanent improvements to a building should allow for whatever future use one can foresee.

[Tin Can]

6 feet from edge of sink to any electricity

arms length

[Drew Wiley]

I built my darkroom to code, even had the panel and wiring run to it done by the company industrial electrician (and yes, that business was classified as a heavy industry due to its integral mill with 880 incoming voltage). Wanted ample power for my own shop tools too, in an adjacent section. I did all the minor wiring and fixtures myself. I knew how to do the rest; but in this city, any kind of shop or chemical business license per se is subject to fire dept inspections should they choose to do so. Normally, it's just a shake-down: pay an annual fee, and nobody ever shows up to check anything. That's why all kinds of terrible fires occur in makeshift warehouse art colonies or disguised meth labs. Plus half of the building inspectors are corrupt and expect a bribe, just like in most big cities. But I got lucky at the start and had an honest young inspector particularly intrigued in how I was doing things because he was planning on making his own darkroom.

[domaz]

An interesting approach. Thank you.

To pile on your options, I plan on just putting in a combo AFCI/GFCI breaker in my panel for my darkroom circuit. This protects all the outlets from both arc faults (the ones that cause fires) and ground faults (the ones that shock you). These breakers are expensive but seem worth it to me, especially having insurance against arc faults since I'm doing the work myself, basically makes the risk of electrical fire nonexistant.

[Luis-F-S]

I have a separate 20A circuit for my enlarger that I shut off when not used. There is a DeVere power stabilizer plugged into this outlet and the enlarger lamped at 1000 W is plugged into the stabilizer. There are two other 20A circuits on GFI outlets, one for the chiller/film dryer and one for the rest of the darkroom. On this circuit is a 4x5 LPL enlarger with one 250 W lamp. The central AC is on a separate feed to the room. Darkroom is 8' x 11' and has 5 LED cans and one strip for general lighting. There is a 60A 220 breaker that feeds this, and a second 60A 220 breaker that feeds the washer/dryer, plate burner (on it's own 20A breaker circuit), dry mount press and upstairs lights/outlets. I'd check with an electrician about local codes.