3Ph/415v Generators for workshop..
Discussion
The rented workshop I have does not have 3 phase and the landowner is not keen on a reconnection (also not sure I want the standing charge/minimum consumption). Workshop is not used full time - probably average around 10 > 15 days a month.
At the moment I end up converting machines to use 220v 3phase via digital inverters but I'm at the work envelope for a couple and need to move up a level. Been looking at generators in the 10 > 15KVA range (but have to admit it's been a finger in the air guesstimate based on anecdotal research and fag packet "calcs" - maximum of say 7HP lathe or 5hp + 2hp mill and not both running at the same time)
Few questions if there are any resident generator experts though:
1) Can you run a welder off a generator safely ?- mate has a 400A TiG; he's not going to be pushing it to its limits though
2) I can go new with something like a KIPOR KDE12STA3 and hit a price point of around 2.5k or do I go second hand (for example watching a 21KVA open frame diesel job which is gradually reducing in price)? I can see the benefit of a warranty etc but is there anything specific that a new one would bring; better control, voltage regulation etc?
3) What are they like maintenance wise?
4) Finally I'm not wrong in assuming I can run one on red diesel am I?
Thanks in anticipation
At the moment I end up converting machines to use 220v 3phase via digital inverters but I'm at the work envelope for a couple and need to move up a level. Been looking at generators in the 10 > 15KVA range (but have to admit it's been a finger in the air guesstimate based on anecdotal research and fag packet "calcs" - maximum of say 7HP lathe or 5hp + 2hp mill and not both running at the same time)
Few questions if there are any resident generator experts though:
1) Can you run a welder off a generator safely ?- mate has a 400A TiG; he's not going to be pushing it to its limits though
2) I can go new with something like a KIPOR KDE12STA3 and hit a price point of around 2.5k or do I go second hand (for example watching a 21KVA open frame diesel job which is gradually reducing in price)? I can see the benefit of a warranty etc but is there anything specific that a new one would bring; better control, voltage regulation etc?
3) What are they like maintenance wise?
4) Finally I'm not wrong in assuming I can run one on red diesel am I?
Thanks in anticipation
Diesels -
Yes run them on red - not on road then you run em on red diesel. All our gensets at work run on red diesel.
Spec for generators - you need to see what loads you are going to run from them - and if you are going to run more than one item at a time.
Is it going to be sole provider of electricity at your site or are you using any other supplies.
You need to remember you are dealing with 415v here and that you need to ensure that your installation complies with the relevant electrical regulations. There must be absolutely no chance of cross connecting your generator with your existing electrical supply.
Earthing - for reasons of safety your generator will need to be properly earthed. Id look at a small electrical installation for this. A proper incoming switchboard that connects to your generator with an RCD isolator and three phase distribution board with suitable circuit breakers. Run out from there to your points of utilisation and have proper 3ph plug socket connections for your equipment.
Cable must be properly rated for current and distance and properly contained. When Ive put in 3 phase generators Ive nearly always put in earth rods and used them to provide an earthing point. Ive kept the 3ph totally separate from the 1ph that was already installed. In interests of safety Ive also put a notice at the incomer utility switch gear that this premises has two sources of power, and indicated where the generator is at.
I see that there are 400A welders that come with a 3ph 15kva generator on board - so id look at using a 20 kva generator. If you are going about putting in a separate generator yourself.
Do you know the price of generators ? you are talking about 3-4 k for a generator, and then id add a few hundred in there to do the electrical installation properly.
Yes run them on red - not on road then you run em on red diesel. All our gensets at work run on red diesel.
Spec for generators - you need to see what loads you are going to run from them - and if you are going to run more than one item at a time.
Is it going to be sole provider of electricity at your site or are you using any other supplies.
You need to remember you are dealing with 415v here and that you need to ensure that your installation complies with the relevant electrical regulations. There must be absolutely no chance of cross connecting your generator with your existing electrical supply.
Earthing - for reasons of safety your generator will need to be properly earthed. Id look at a small electrical installation for this. A proper incoming switchboard that connects to your generator with an RCD isolator and three phase distribution board with suitable circuit breakers. Run out from there to your points of utilisation and have proper 3ph plug socket connections for your equipment.
Cable must be properly rated for current and distance and properly contained. When Ive put in 3 phase generators Ive nearly always put in earth rods and used them to provide an earthing point. Ive kept the 3ph totally separate from the 1ph that was already installed. In interests of safety Ive also put a notice at the incomer utility switch gear that this premises has two sources of power, and indicated where the generator is at.
I see that there are 400A welders that come with a 3ph 15kva generator on board - so id look at using a 20 kva generator. If you are going about putting in a separate generator yourself.
Do you know the price of generators ? you are talking about 3-4 k for a generator, and then id add a few hundred in there to do the electrical installation properly.
Hi, thanks.
It's not the sole supply - there's already a 220v supply and that's handling lighting, smaller tools etc. This will be purely used to power larger machine tools; mill, lathe etc - I'm not going to using anything bigger than 10HP at any one time - and even that's unlikely.
Installation will be discrete, there'll be absolutely no chance of a cross connection as we'll be running completely new and separate wiring and panel.
I've been watching prices for the last 2 - 3 months; huge difference between an open framed, skid mounted thing that's been backup at a small workshop etc and nice modern painted item on a fast tow trailer. That's the dilemma - I can get the KVA at even sub 1.5k but it'll be an older generator or I can hit 2.5k for 12KVA modern set (the 400A welder will never be used at full capacity + it's a nice to have not an absolute).
Cost is a factor but it'll still be cheaper than running 3 phase connection from the local supplier and I'm likely to have to move in a couple of years so having "portable" 3 phase is very attractive.
It's not the sole supply - there's already a 220v supply and that's handling lighting, smaller tools etc. This will be purely used to power larger machine tools; mill, lathe etc - I'm not going to using anything bigger than 10HP at any one time - and even that's unlikely.
Installation will be discrete, there'll be absolutely no chance of a cross connection as we'll be running completely new and separate wiring and panel.
I've been watching prices for the last 2 - 3 months; huge difference between an open framed, skid mounted thing that's been backup at a small workshop etc and nice modern painted item on a fast tow trailer. That's the dilemma - I can get the KVA at even sub 1.5k but it'll be an older generator or I can hit 2.5k for 12KVA modern set (the 400A welder will never be used at full capacity + it's a nice to have not an absolute).
Cost is a factor but it'll still be cheaper than running 3 phase connection from the local supplier and I'm likely to have to move in a couple of years so having "portable" 3 phase is very attractive.
A portable one is easily thieved - lots of market out there for gensets. Id stick to a skid one, also look at old backup gensets - they will have been sitting there hardly used - as long as the hours are low and it looks like its been reasonably well kept - general maintenance itesm like aircleaners and air fuel filters all look reasonably new. The visual look can quickly be addressed so no worries there. If you get a skid one thats easily lifted onto a trailer by a forklift as and when needed that suit suit you. Trailer one Hmmm also with a trailer one it will have proabably been used a lot more - Ive found the trailer ones tended to have the higher hours.
You say that your not going to use it much - need to be aware of fuel issues - diesel goes off so Id look at some form of diesel treatment. Maybe even look at how you store your fuel.
Diesel generators also like to be kept warm usually have a pump and water heater somewhere and the temperature is kept to around 40 - 50 degrees - makes for easier starting and protects against frost. They will have a connection point for a mains supply to enable you to keep the heater powered and the battery charged.
Your ratings also need to be checked - start up currents for your welder and other equipment needs to be taken into consideration as you dont want you set to trip when welding. Generators can and do trup out on under frequency quite easily if you try to start larger loads on them. its all very well matching normal operarting currents. but you have to start the load. And with welders you are drawing an arc quite a few times when you weld that it can get close to the generator ratings if you dont spec your engine up to the task in hand.
You say that your not going to use it much - need to be aware of fuel issues - diesel goes off so Id look at some form of diesel treatment. Maybe even look at how you store your fuel.
Diesel generators also like to be kept warm usually have a pump and water heater somewhere and the temperature is kept to around 40 - 50 degrees - makes for easier starting and protects against frost. They will have a connection point for a mains supply to enable you to keep the heater powered and the battery charged.
Your ratings also need to be checked - start up currents for your welder and other equipment needs to be taken into consideration as you dont want you set to trip when welding. Generators can and do trup out on under frequency quite easily if you try to start larger loads on them. its all very well matching normal operarting currents. but you have to start the load. And with welders you are drawing an arc quite a few times when you weld that it can get close to the generator ratings if you dont spec your engine up to the task in hand.
GnuBee said:
The rented workshop I have does not have 3 phase and the landowner is not keen on a reconnection (also not sure I want the standing charge/minimum consumption). Workshop is not used full time - probably average around 10 > 15 days a month.
If it's of interest I had my supply upgraded to 3 phase last year. It cost £680 plus VAT and I retained my existing fixed rate and standing charge.C Lee Farquar said:
If it's of interest I had my supply upgraded to 3 phase last year. It cost £680 plus VAT and I retained my existing fixed rate and standing charge.
I've spoken to the landowner and he's not prepared to allow me to get it re-connected <- yes this is the supreme irony; the workshop is on ex-commercial premises that used to have 3 phase.That combined with the warning that he's expecting to sell within the next 2 years is really dictating the direction here.
This makes him sounds worse than he is; we pay very little for our facilities (pay nothing for electricity or water currently for example) and have the advantage that like many farmers he's armed and always suspicious of people on or near his land.
only issue with open frame skid gensets is they tend to be somewhat noisy, fine if you can park it out the way, but you really don't want to be next to one.
More modern enclosed ones are much easier to live with, but remember, they still need to be well ventilated - 20Kva gen will be putting out ~40Kw of heat (between the radiator and exhaust), that said, this can be quite useful for heating a shed in the winter!
400A two phase welder - what exactly are we looking at here?
if it's an industrial type genuine 400A, then 20Kva is not going to cut it, as you have to consider that they are not a 3 phase load, it's running 1 phase delta - 415V, and the genset is rated on loading all 3 phases reasonable equally.
400A @ 60V is 24Kw just to start with.
More modern enclosed ones are much easier to live with, but remember, they still need to be well ventilated - 20Kva gen will be putting out ~40Kw of heat (between the radiator and exhaust), that said, this can be quite useful for heating a shed in the winter!
400A two phase welder - what exactly are we looking at here?
if it's an industrial type genuine 400A, then 20Kva is not going to cut it, as you have to consider that they are not a 3 phase load, it's running 1 phase delta - 415V, and the genset is rated on loading all 3 phases reasonable equally.
400A @ 60V is 24Kw just to start with.
Scuffers said:
only issue with open frame skid gensets is they tend to be somewhat noisy, fine if you can park it out the way, but you really don't want to be next to one.
More modern enclosed ones are much easier to live with, but remember, they still need to be well ventilated - 20Kva gen will be putting out ~40Kw of heat (between the radiator and exhaust), that said, this can be quite useful for heating a shed in the winter!
400A two phase welder - what exactly are we looking at here?
if it's an industrial type genuine 400A, then 20Kva is not going to cut it, as you have to consider that they are not a 3 phase load, it's running 1 phase delta - 415V, and the genset is rated on loading all 3 phases reasonable equally.
400A @ 60V is 24Kw just to start with.
I know nothing about welders so all I can tell you is it's some huge behemoth of a blue box, previously used fabricating parts for Lister cars. The welder support is very much a nice to have; I don't need it as my interest here is purely in supporting my machinery - supporting a welder is purely something for my friend - he'd be using it to do typical car bodywork type activity; not welding small container ships together.More modern enclosed ones are much easier to live with, but remember, they still need to be well ventilated - 20Kva gen will be putting out ~40Kw of heat (between the radiator and exhaust), that said, this can be quite useful for heating a shed in the winter!
400A two phase welder - what exactly are we looking at here?
if it's an industrial type genuine 400A, then 20Kva is not going to cut it, as you have to consider that they are not a 3 phase load, it's running 1 phase delta - 415V, and the genset is rated on loading all 3 phases reasonable equally.
400A @ 60V is 24Kw just to start with.
The heat point is valuable - I was hoping it would be like that as I'd be interested in leveraging some of that waste heat for the workshop.
The impression I get from all (the very helpful replies for which I'm very greatful) is that things start getting demanding if I pursue the favour to a friend with his TiG tank.
The noise thing is most definitely a consideration but this is an ex commercial site, a skid mounted set would be outside (under cover).
GnuBee said:
I know nothing about welders so all I can tell you is it's some huge behemoth of a blue box, previously used fabricating parts for Lister cars.
Not a miller Dialarc like this is it:
I've got one which i run on single phase, on the 200A range it will weld up to 8-10mm Ally and it will pull around 60AMPS AC single phase - never dared try it on the 400amp range. They are pretty ancient and inefficient - a modern switching one uses a fraction of the power.
A guy that used to work for me borrowed my Honda generator and old 160A pick-a-brand gas welder to do some small bits of work on his M3, due to the same situation. As has been said, it isn't ideal, but not impossible. I don't think I'd attempt any heavy or long duration work though. Another friend that was a engineering welder for 20 years did the actual welding for him, and had there been any complications, high risk or poor supply, neither of them would have been satisfied so on that grounds I'd say it's fine if you're in a pinch.
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