How long will dimmer last?

Status
Not open for further replies.

GerryB

Senior Member
I need to dim the lights for a church Christmas show. How long do you think a 600 or 1000 watt dimmer last or even work with 1800 watts on it? (this is not a trick question:D)
 

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
You're asking for an opinion. OK. My opinion is an interval of time measured in seconds.

The 1800 Watt load current travels through a silicon semiconductor. Silicon semiconductors have a very low tolerance of overloads.

(Making an assumption here) How about two extension cords with two dimmers?
 

kwired

Electron manager
Location
NE Nebraska
You're asking for an opinion. OK. My opinion is an interval of time measured in seconds.

The 1800 Watt load current travels through a silicon semiconductor. Silicon semiconductors have a very low tolerance of overloads.

(Making an assumption here) How about two extension cords with two dimmers?
If he has 1800 watts and 600 watt dimmers, he probably would want at least three cords and three dimmers;)

I would say only lasting for an interval measured in seconds is possible but I am optimistic that it could possibly even be measured in hours. To some extent it kind of will depend on what level of dimming is involved and for how long, and will depend on how much cooling is provided at the dimmer location:happyyes:

I would recommend having spares on hand and a method of quick change so it doesn't interrupt the program, or a 2000 watt dimmer.
 

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
To some extent it kind of will depend on what level of dimming is involved and for how long, and will depend on how much cooling is provided at the dimmer location:happyyes:.
Yup. The less dimming, the faster the dimmers will immolate themselves.
 

G._S._Ohm

Senior Member
Location
DC area
If you only need to dim over a limited range you could put a resistance/reactance across the dimmer so it only sees a portion of the total load current.

If noise is not a problem use an aluminum/copper heat sink with forced air cooling across the dimmer (remove the plastic case so all the components get airflow). These dimmers hardly have any heat-sinking.
Oil cooling is even better but it may be impractical here.

You want to maintain the same mounting bracket temp. as when it is handling its rated load.
 
Last edited:

hillbilly1

Senior Member
Location
North Georgia mountains
Occupation
Owner/electrical contractor
Two 1000 watt ROTARY dimmers wired in parralel with a rubber band stretched across the knobs, both will turn at same rate, hopefully maintaining a somewhat equal dimming capacity. With the 1000 watt dimmers, they should tolerate some unbalance.
 

GerryB

Senior Member
If he has 1800 watts and 600 watt dimmers, he probably would want at least three cords and three dimmers;)

I would say only lasting for an interval measured in seconds is possible but I am optimistic that it could possibly even be measured in hours. To some extent it kind of will depend on what level of dimming is involved and for how long, and will depend on how much cooling is provided at the dimmer location:happyyes:

I would recommend having spares on hand and a method of quick change so it doesn't interrupt the program, or a 2000 watt dimmer.

Didn't know about 2000 watt dimmers. Sounds pricey. I'll probably take out some lamps. These are six ceiling fans with five lights each, they look like 60 watt candalabra.
 

gadfly56

Senior Member
Location
New Jersey
Occupation
Professional Engineer, Fire & Life Safety
Didn't know about 2000 watt dimmers. Sounds pricey. I'll probably take out some lamps. These are six ceiling fans with five lights each, they look like 60 watt candalabra.

Use dimmable CFL's, or make 4 of the lamps regular CFL's and leave one incandescent. You'll be able to dim all the lamps. Don't know why, but it works. At least for theatrical dimmers, which at the time I was doing them were just back-to-back SCR's.
 

iceworm

Curmudgeon still using printed IEEE Color Books
Location
North of the 65 parallel
Occupation
EE (Field - as little design as possible)
Didn't know about 2000 watt dimmers. Sounds pricey. I'll probably take out some lamps. These are six ceiling fans with five lights each, they look like 60 watt candalabra.

Gerry -
A couple of thoughts:
This is a free labor, parts included for the kiddies church show. And you already have the cheap dimmers. And it is a one time deal.

First:
How is it you know the 2000W dimmer is pricey? Did you call or go look? I don't know what your definition of pricey is, but if you don't check how would you know? $50 for the right parts could solve a lot of headache. Just think what the kids will feel like when this DIY cluster-ball goes up in smoke and fire right in the middle of Silent Night.

Second:
You could get lucky. I'd be a bit surprised if all six fans are on the same 120VAC circuit. That's pushing a 20A circuit right to the limit. Have you looked at the panel to see if the fans are split into two circuits? Are there two switches?

Either of these two would make life a lot easier.

How long will they last?
Well, with the wind out of the east at 5mph, ambient 25C, RH 90%, night exhibit, no moon, CAVU, I would estimate just long enough to get the heatsinks hot enough to burn the snot out of your fingers just before they disapear in a cloud of extraneous energy emmission.

ice (extraneous energy = heat, light, smoke)
 

kwired

Electron manager
Location
NE Nebraska
Didn't know about 2000 watt dimmers. Sounds pricey. I'll probably take out some lamps. These are six ceiling fans with five lights each, they look like 60 watt candalabra.

If they are ceiling fans, buy some of those wireless remote units to put in each fan, that have light dimming capabilities.

2000 watt dimmer may be pricey, but how much is 600 watt dimmers and additional wiring going to cost? Remember also that if you put them in one box they need derated.
 

GerryB

Senior Member
Gerry -
A couple of thoughts:
This is a free labor, parts included for the kiddies church show. And you already have the cheap dimmers. And it is a one time deal.

First:
How is it you know the 2000W dimmer is pricey? Did you call or go look? I don't know what your definition of pricey is, but if you don't check how would you know? $50 for the right parts could solve a lot of headache. Just think what the kids will feel like when this DIY cluster-ball goes up in smoke and fire right in the middle of Silent Night.

Second:
You could get lucky. I'd be a bit surprised if all six fans are on the same 120VAC circuit. That's pushing a 20A circuit right to the limit. Have you looked at the panel to see if the fans are split into two circuits? Are there two switches?

Either of these two would make life a lot easier.

How long will they last?
Well, with the wind out of the east at 5mph, ambient 25C, RH 90%, night exhibit, no moon, CAVU, I would estimate just long enough to get the heatsinks hot enough to burn the snot out of your fingers just before they disapear in a cloud of extraneous energy emmission.

ice (extraneous energy = heat, light, smoke)

OK, point made. It is actually one ckt for the fans on a speed control and a different ckt for the lights. I have to try gadfly's suggestion to see if it works, and then I will buy the tax deductable charitable donation 50 dollar 2000 watt dimmer.
 

iceworm

Curmudgeon still using printed IEEE Color Books
Location
North of the 65 parallel
Occupation
EE (Field - as little design as possible)
OK, point made. It is actually one ckt for the fans on a speed control and a different ckt for the lights. I have to try gadfly's suggestion to see if it works, and then I will buy the tax deductable charitable donation 50 dollar 2000 watt dimmer.
Good Luck with your endeavor. I sincerely hope it is $50 and not $150.

My usual luck is to go into these figuring. "Hey, its only $100 and a half a day." I end up with $500 and two days and I'm looking for my short sword to get out of it.

I truly wish you better luck than that.

ice
 

PetrosA

Senior Member
Plus keep in mind that for a 200W dimmer, you're probably going to need two gangs. If you already have a single switch mounted, you're good to go but if it's a ganged switch, you're in trouble.
 

G._S._Ohm

Senior Member
Location
DC area
pricey

pricey

Nextag has half costing between $126 and $259, retail.
I don't know what you're getting if you pay outside that range.
 

gadfly56

Senior Member
Location
New Jersey
Occupation
Professional Engineer, Fire & Life Safety
Nextag has half costing between $126 and $259, retail.
I don't know what you're getting if you pay outside that range.

If brand is any indicator of quality, the $64 dollar model in iwire's URL was from Lutron.
 

G._S._Ohm

Senior Member
Location
DC area
If brand is any indicator of quality, the $64 dollar model in iwire's URL was from Lutron.
Well, it is an outlier, only 1 in a sample of 14 this cheap.
I don't know what to make of this. Maybe it wasn't selling well, for who knows what reason. Maybe there are usage restrictions.

Generally there is supposed to be zero correlation between price and quality.






Lutron C-2000-BE Beige Centurion Traditional / Classic 120 Volt 2000 Watt Incand
120 Volt 2000 Watt Incandescent or Halogen Single Pole Large Control Preset Dimmer with Rotate On/Off from the Centurion CollectionThis rota ..Read More


Keep this on my Radar
| More Like This

 
Last edited:
Status
Not open for further replies.
Top