Furse Dimmer, 5amp socket Power Question

[GEN]

Hi Guys I am glad I have found this website it looks great... Rite I just need some help if possible. On Our stage we have an old Furse system. There are in total 48 sockets on our lighting bars all are 5 Amp sockets. Now I am going to be buying some PARs and mkore lights . Does anyone know how many 1000W PARs I could rig up to this system and run at the same time?

[son of lx dad]

From the little information you have given the "grasped from thin air theoretical" answer is:-

 

48

 

i.e. one per outlet being that they are only 5amp outlets.

 

The important bit you have not mentioned is the number of dimmers you have and the size of the supply to those dimmers......

 

The number of holes is irrelevant. You could plug 500 circuits in but if you only have an Act6 on 13amp at the other end not much is going to happen. More information required.

[GEN]

Thanks for your reply and im sorry for the lack of detail... Rite there are 4 dimmers and the system is run on LC 10 amp fuses? Now does that make any difference?

[MrBoomal]

4 dimmers with a maximum rating of 10 amps per channel will allow you to rig 8 pars (assuming you mean 1000w Par 64 lamps). 2 per dimming channel. That is assuming your dimmers are running off a suitable supply, and not just plugged into a 13 amp outlet.

 

Right is spelt right. Or in your case wrong.

[GEN]

thanks for your reply this really helps. P.s I do know how right is spelt

 

thanks again

 

A concurrent post has been automatically merged from this point on.

 

The dimmers are running of a suitable supply. And they are PAR64 100W lamps I want to use with the system? Does this mean I can only run up to a total of 8 on the whole system? Is there anyway I can run more than this or not?

[springgrove]

thanks for your reply this really helps. P.s I do know how right is spelt

 

thanks again

 

A concurrent post has been automatically merged from this point on.

 

The dimmers are running of a suitable supply. And they are PAR64 100W lamps I want to use with the system? Does this mean I can only run up to a total of 8 on the whole system? Is there anyway I can run more than this or not?

Hi GEN

 

I am not sure we are all talking about the same thing here. You have various points of limitation:

A 5A socket can only run one 1000W PAR64. (1000W, rather than 100W)

Each dimmer channel, if it is fused at 10A can only run two 1000W lamps.

If the supply to a dimmer rack is, say 32A, you can only run 6 1000W lamps (12 for a 63A supply) ... approx

There may also be a total limit on the supply for the total of all the dimmer racks.

 

When you say four dimmers, do you mean four channels, or four dimmer racks?

 

Nigel

[GEN]

Ah this is now starting to make sence, thanks Nigel, yes I did mean 1000W PARs im just crap at typing fast ** laughs out loud **. Anyway, I meant 4 Channels, they are on the inside of the dimmer. Do you know where I can find out how much the total limit on the supply? Would it be inside the on/off leaver swich box which is also housed above the dimmer rack? I only intend to run one par64 1000W per 5amp socket although I would like to use more than 8 on the overall system, is there anyway this can be done?

 

Thanks again

[MrBoomal]

There's no way you can run more of this system (not at full power anyway) , and there is a reasonable chance that you may have to run less. Are your dimmers plugged into any kind of socket, or are they hard wired into the mains ?

[bruce]

I guess the bottom line is that we can't make any definitive statements based on the information given. While all of the answers above are correct, we don't know the details of the installation. Without seeing some drawings, or photos, or a detailed spec of how it all fits together, it would be rash to give a definitive answer.

 

But one thing to bear in mind is that Furse ceased trading in 1988 - which means that the installation is at least 21 years old, and most probably much older. The definitive answer can only be "ask a qualified electrician to come in and inspect the system"

 

Bruce.

[springgrove]

Ah this is now starting to make sence, thanks Nigel, yes I did mean 1000W PARs im just crap at typing fast ** laughs out loud **. Anyway, I meant 4 Channels, they are on the inside of the dimmer. Do you know where I can find out how much the total limit on the supply? Would it be inside the on/off leaver swich box which is also housed above the dimmer rack? I only intend to run one par64 1000W per 5amp socket although I would like to use more than 8 on the overall system, is there anyway this can be done?

 

Thanks again

If you've only got four 10A channels of dimming, then 8 is going to be your limit. It is possible to get 500W PAR64 lamps, or PAR56 lamps are usually 300W, if you want more flexibility.

 

You could extend number of channels by using extra portable dimmer packs plugged into 13A sockets, e.g. Pulsar minipacks. Zero88 Alphapacks.

 

There will probably be a fuse or circuit breaker in or on the switch box with a rating on it.

 

Nigel

[GEN]

I have an electrician coming to look at it on wednesday... I just wanted to know about how much I can power on it as im new to this system. Yes it is very very old and the school is looking at getting a new one done by CCT but untill then I just got to kind of cope with this one. As far as I know the people who used to use this system within the school once had about 20 PAR64's running on the system. This is why im very confused now. The Dimmer is hardwired into the mains.

[MrBoomal]

I'm rather confused about how your system is set up. You have 48 sockets on your bars but only 4 dimming channels. What are the inlets coming off the bars into your dimmer room? Do you have 48 15 amp plugs ? Or 8 socapex cables (Socapex will be a connector with 19 holes or pins ) ?

 

I'm pretty sure you haven't got 48 sockets hard wired into 4 dimmers.

[GEN]

Rite im going to type a full description of the system tomorrow. So far thanks for your help guys

[bruce]

... a picture speaks a thousand words. Post some photos.

[JohnMac]

Here we go again :D

 

Guess the electrical installation....

 

Just because the dimmer has 4 x LC 10 fuses does not necessarily mean that you can draw 40A from the supply.

The dimmer system may be protected / limited by an overall fuse which may be significantly less.

 

I have worked in several schools where although the individual 6 channel dimmer packs were fitted with 32A CEE connectors, complete with Isolators, Circuit protection and Earth protection, the incoming supply (i.e. size of cable) was limited by its protective circuit breaker of only 63A or less.

 

Just because 3 x 32A sockets were there, it did not mean that there was 96A available.

 

Any current rating on an electrical device is its' designed maximum rating, not what is currently there. :D

 

One installation had 4 x 6 x 2Kw Dimmers each with a 32A connector, but because of the limitation on the mains distribution board, each dimmer rack only had a 15A circuit breaker. (3.5Kw max! Which on a 'first pass', looked like 12Kw).

 

I am extremely concerned that in this and other threads we are being given an incomplete description, fuzzy pictures and asked to guess the parts and what is happening. :)

 

Electricity at Work Regulations make it quite clear that only Competent Persons should be involved with any work activity near or on electrical systems.

 

ELECTRICITY WILL KILL YOU, if you get too close, or do something wrong.

 

Danger is defined as risk of injury, and injury is defined in terms of certain classes of potential harm to persons, namely electric shock, electric burn, fires of electrical origin, electric arcing, and explosions initiated or caused by electricity.

 

Whilst encouraging people to ask for advice and information, it is essential that if you don't know Ohms law, and Power formulas, and you don't know what you are doing leave well alone.

 

Competence

 

Don’t take on work beyond your capabilities.

You need the right knowledge, experience and understanding of the system to be worked on.

Adequate knowledge of electricity.

Understanding of the hazards which may arise during the work and the precautions which need to be taken.

Know and recognise when you are out of your depth, Stop and make safe.

You should know the risks associated with your work and know how to deal with them.

Be sure to ask for advice and information where you need it.

 

Given recent issues, this is not aimed at anyone, or at any age group, Yep! I do fall into the grumpy old man category

but electrical safety is vital to both young and old.

 

John Mac.