Providing Lighting from Motor Supply

[lozarus]

Apologies for the vagueness in the title. You'll have to forgive my ignorance on the below too - I'm only just touching on 'industrial' as my work is generally more ' commercial'.

I'm faced with a small pump house - rainwater sumps which takes the site rainfall and pumps it out. As an aside - the pumps and their control gear are lovely - still sporting their paper manufacturer tags reading November 1963.

The pump equipment gets a 60a 3ph supply via PILC from the pull out ABB fuse carrier assembly in the intake room behind the substation a good distance away. The PILC terminates in a large isolator beneath an equally dated BILL 3ph fuse board...dated but in perfect condition and complete with Asbestos Clearance paperwork confirming the pads have been removed and replaced with alternative inserts.

6 fuses and carriers in here. There's 2 pumps so simply one fuse per phase per pump. No spare fuseways. I haven't checked the size of the fuse wire but until I decide how to proceed with this job, that's kind of by the by.

The job is to simply provide an internal LED strip light to allow maintenance - and provide an external PIR operated light. There was an internal light in here before, however, interestingly this was supplied completely separate to the 60a 3ph supply to this building and came in via a very long, buried 1" conduit in VIR singles fed from a small services board in the intake room. This circuit has long since failed. The conduit seems to have rotted as it's collapsed and I can't pull anything through.

Protection wise I don't see any real issue with taking a feed from one of the existing, used fuseways in the BILL fuse board into a separate RCBO or even RCD FCU and supplying the lights from here. I know some me people don't like 2 different supplies taken from one fuseway...but I don't see an issue with it.

My question is....will adding a load to one of these fuses that's currently supplying a phase of the motor, cause any issues with relation to load balancing etc?

Hope this makes sense. Any thoughts welcomed.

 

[cireland]

Is there a neutral?

 

[mainline]

Apologies for the vagueness in the title. You'll have to forgive my ignorance on the below too - I'm only just touching on 'industrial' as my work is generally more ' commercial'.

I'm faced with a small pump house - rainwater sumps which takes the site rainfall and pumps it out. As an aside - the pumps and their control gear are lovely - still sporting their paper manufacturer tags reading November 1963.

The pump equipment gets a 60a 3ph supply via PILC from the pull out ABB fuse carrier assembly in the intake room behind the substation a good distance away. The PILC terminates in a large isolator beneath an equally dated BILL 3ph fuse board...dated but in perfect condition and complete with Asbestos Clearance paperwork confirming the pads have been removed and replaced with alternative inserts.

6 fuses and carriers in here. There's 2 pumps so simply one fuse per phase per pump. No spare fuseways. I haven't checked the size of the fuse wire but until I decide how to proceed with this job, that's kind of by the by.

The job is to simply provide an internal LED strip light to allow maintenance - and provide an external PIR operated light. There was an internal light in here before, however, interestingly this was supplied completely separate to the 60a 3ph supply to this building and came in via a very long, buried 1" conduit in VIR singles fed from a small services board in the intake room. This circuit has long since failed. The conduit seems to have rotted as it's collapsed and I can't pull anything through.

Protection wise I don't see any real issue with taking a feed from one of the existing, used fuseways in the BILL fuse board into a separate RCBO or even RCD FCU and supplying the lights from here. I know some me people don't like 2 different supplies taken from one fuseway...but I don't see an issue with it.

My question is....will adding a load to one of these fuses that's currently supplying a phase of the motor, cause any issues with relation to load balancing etc?

Hope this makes sense. Any thoughts welcomed.

Adding a led strip isn't going to make much difference to the 3 phase balance.
No real difference to where a 3 phase machine uses one phase to feed the control panel.

 

[MikeM3]

Apologies for the vagueness in the title. You'll have to forgive my ignorance on the below too - I'm only just touching on 'industrial' as my work is generally more ' commercial'.

I'm faced with a small pump house - rainwater sumps which takes the site rainfall and pumps it out. As an aside - the pumps and their control gear are lovely - still sporting their paper manufacturer tags reading November 1963.

The pump equipment gets a 60a 3ph supply via PILC from the pull out ABB fuse carrier assembly in the intake room behind the substation a good distance away. The PILC terminates in a large isolator beneath an equally dated BILL 3ph fuse board...dated but in perfect condition and complete with Asbestos Clearance paperwork confirming the pads have been removed and replaced with alternative inserts.

6 fuses and carriers in here. There's 2 pumps so simply one fuse per phase per pump. No spare fuseways. I haven't checked the size of the fuse wire but until I decide how to proceed with this job, that's kind of by the by.

The job is to simply provide an internal LED strip light to allow maintenance - and provide an external PIR operated light. There was an internal light in here before, however, interestingly this was supplied completely separate to the 60a 3ph supply to this building and came in via a very long, buried 1" conduit in VIR singles fed from a small services board in the intake room. This circuit has long since failed. The conduit seems to have rotted as it's collapsed and I can't pull anything through.

Protection wise I don't see any real issue with taking a feed from one of the existing, used fuseways in the BILL fuse board into a separate RCBO or even RCD FCU and supplying the lights from here. I know some me people don't like 2 different supplies taken from one fuseway...but I don't see an issue with it.

My question is....will adding a load to one of these fuses that's currently supplying a phase of the motor, cause any issues with relation to load balancing etc?

Hope this makes sense. Any thoughts welcomed.

You have probably fixed this by now, but if you haven't, then you need
to connect 3 lights separately, one to each phase, then connect another
wire to the other side of each light, as neutrals, these 3 neutral wires
must be joined together, like a star connection, this is the way to power
lights from a 3phase system without a neutral.

Mike.

 

[mickegh]

You have probably fixed this by now, but if you haven't, then you need
to connect 3 lights separately, one to each phase, then connect another
wire to the other side of each light, as neutrals, these 3 neutral wires
must be joined together, like a star connection, this is the way to power
lights from a 3phase system without a neutral.

Mike.

Hmm dont like the sound of that

 

[westward10]

I have done this in classroom situations with tungsten lamps but in 40+ years in the industry I have never seen it put into practice.

 

[MikeM3]

Hmm dont like the sound of that

That is how we did it on tower cranes, 1200 watt Halogen lights,
many years ago, might not be allowed today, of course.

Mike

 

[lozarus]

Thanks all. As it happens - I haven't done this yet. The building got closed for other works and I'm awaiting a return date.

As it happens there was a neutral in there - but I appreciate this explanation - it makes sense and I'll stick it in my memory!

 

[Simon47]

You have probably fixed this by now, but if you haven't, then you need
to connect 3 lights separately, one to each phase, then connect another
wire to the other side of each light, as neutrals, these 3 neutral wires
must be joined together, like a star connection, this is the way to power
lights from a 3phase system without a neutral.

OK for a simple load.
What happens with (say) SMPS LED drivers ? I'd guess :
Loads aren't perfectly balanced, especially during startup, so one takes less current than others.
So the "neutral" point shifts taward the other phases.
As neutral point shifts, currents change an we know that with an SMPS it has a negative relationship - more voltage results in less current.
So the neutral point shifts more, and more, and more.
Eventually it'll settle with two lamps sharing a phase-phase voltage (i.e. undervoltage), whike the 3rd light is well overvoltage.

As the 2 undervoltage lamps won't be perfectly balanced either, same thing will apply so they won't actually be balanced either.

So these days, if there is no neutral then you'll need to connect direct across the phases with higher voltage lamps - or use a step down tx across 2 phases.

Since the OP does have a neutral, then it's a lot simpler.

Another thought is a practical one. So you wire a light to one of the motor circuits - what happens when that circuit needs maintenance ? I'd suggest you need two lights, one off each motor circuit.