Low voltage dimmer switch ... i think

[sparkdawg]

Hi, im hoping someone could help me as ive never come across a dimmer switch like this, its a bit before my time. Ive upgraded some lights for a client in a bowling halls lounge, there is 230v supplying the luminaires and im fairly sure that they have used a low voltage dimmer switch. My client would like me to upgrade the switch but I am unsure what sort of switch I could use to replace the old dimmable one. The lights that I have replaced are non dimmable. Any advice on what switch I could use would be appreciated.

 

[telectrix]

those switches send a variable voltage 0 -10V to dimmable ballasts. the cable is not suitable for 230V. you'll need to rewire switches to lights in appropriate cable. then any 230V switches can be fitted.

 

[James]

I suspect that there is a multi dimming supply unit that takes the inputs from these dimmer pot’s and modulates the power before sending it off to the banks of lights. You need to find the device on the end of that multi core cable.
If the lights you are using to replace originals ar non dimmable, you could possibly use a bank of low voltage contactors and any switch you like.
I doubt you can use the original switch wire for mains voltage, however you might be lucky.

 

[Lucien Nunes]

Well it's one of the above two options! Either each luminaire contained the dimming electronics e.g. as part of its ballast, sending the analogue control voltage to the wall panel via a separate cable, or there is a dimmer pack somewhere in the building feeding the luminaire points.

If you are lucky and there is a dimmer pack that has a non-dim setting, you might be able to select that on the channels that now have non-dimmable lights and avoid changing any wiring. A non-dim setting makes the channel function as a solid-state relay, going cleanly from completely off to full on at some point in the dimmer control's travel. Non-dim is not 100% equivalent to a contactor or switch as the triac is still in circuit, so you would need to check compatibility with the new lights. If no non-dim setting is available, there are electronic workarounds, so let's see what lights and dimmers are involved first...

 

[sparkdawg]

Well it's one of the above two options! Either each luminaire contained the dimming electronics e.g. as part of its ballast, sending the analogue control voltage to the wall panel via a separate cable, or there is a dimmer pack somewhere in the building feeding the luminaire points.

If you are lucky and there is a dimmer pack that has a non-dim setting, you might be able to select that on the channels that now have non-dimmable lights and avoid changing any wiring. A non-dim setting makes the channel function as a solid-state relay, going cleanly from completely off to full on at some point in the dimmer control's travel. Non-dim is not 100% equivalent to a contactor or switch as the triac is still in circuit, so you would need to check compatibility with the new lights. If no non-dim setting is available, there are electronic workarounds, so let's see what lights and dimmers are involved first...

Hi there,

firstly thank you for taking time out to give me some help on this. I’ve been an electrician for 3 years now and I’ve mostly worked on new builds, so this is a learning curve for me, and your advice is greatly appreciated.
I have located the bank of dimmable relays. They do have a bypass switch on the module itself. Below is a photo of the bank
[automerge]1601748227[/automerge]

I suspect that there is a multi dimming supply unit that takes the inputs from these dimmer pot’s and modulates the power before sending it off to the banks of lights. You need to find the device on the end of that multi core cable.
If the lights you are using to replace originals ar non dimmable, you could possibly use a bank of low voltage contactors and any switch you like.
I doubt you can use the original switch wire for mains voltage, however you might be lucky.

Hello there,

thank you for taking time out to reply and giving me some valuable advice on the matter. There is a bank of dimmable modules like you said, and I may have to go with your idea of using the contractor for the switching.

 

[James]

I think your best bet would be to buy a replacement dimmer switch that is compatible

 

[Marvo]

Well they've got a bypass button and a bypass trimmer so you might be lucky and still be able to use them as a basic switch. If your new luminaires are LED you might find they present insufficient load for the dimmer circuitry to be stable so maybe wire all the new lights on to just one or two of the dimmer modules first.
[automerge]1601750282[/automerge]

I think your best bet would be to buy a replacement dimmer switch that is compatible

He say the new lights he installed are non-dimmable.

 

[Lucien Nunes]

Ah, good old Electrosonics. Were the original lights fluorescents with separately-fed filament transformers? If so, each channel has both a dimmer output and a relay output that switches on at any brightness above zero. You would be able to connect the new fittings to the relay circuit (ignoring the actual dimmer output) and they will respond correctly to the fader being above zero, with no compatibility problems and no minimum load requirement (unless there's a suppression capacitor across the relay contacts, which might cause some LEDs to flash when off.)

If there's no separate relay output, they might still have bypass relays on the dimmer circuits. In this case you could connect the fittings to the dimmer outputs but unhook the triac connection, in which case the bypass relay will switch them on cleanly at the bypass level set point.

I might have the manual for these somewhere but there were many different types of module.

 

[Lucien Nunes]

Also, if you are in the process of removing and throwing out externally dimmable fluorescent battens that might still be operational, I would be interested to see if it was possible to save them. I have a 1960s thyratron fluorescent dimmer that I would like to set up as a demonstration but don't presently have any fluos with suitable gear. I think the type I need are ballasted by a semi-resonant transformer or choke, with the separate filament transformer, originally made by Atlas but any make will probably do.