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Guineafowl
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Yes, 1/3 output per phase.
This is the one we have. One 16A blue socket per phase, protected by a 16A RCBO. Best to balance the phases if possible.
This is the one we have. One 16A blue socket per phase, protected by a 16A RCBO. Best to balance the phases if possible.
Chippie
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Make sure there is access to the Neutral on the alternator for single phase…. ( Star point..) power available will be 1/3 of the output in 3 ph…
Guineafowl
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Good point - might be worth a look in the connection box to see how it’s configured. Also see if earth is tied to chassis and neutral.
brightspark
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what are the 3 phase sockets on it 4 pin or 5. if 5 it has 3 phase neutral and earth . just use 1 of the phases and the neutral giving 240v single phase
angellonewolf
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could it have 5 pin but one not connected ?
brightspark
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hardly likely
not done it yet
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No, it’s not “just a case of”. But I’m not a leccy.
Yes, taking off one phase would be 7kW but extracting 7kW from only one phase would leave the other two phases out of balance. Not a good way to use a generator - think here why housing estates, fed from a single transformer, are fed from the three different phases along each street.
Large buildings are not fed on one phase only. It is to balance the system, as far as possible.
Best to enquire how much can be taken, from only one single phase, and follow the guidelines.
Chippie
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Yes…think of how houses are connected in your street….although the loads presented to the phases may differ depending on whether they’re watching Corrie or boiling the kettle/ doing laundry…feeding the cat…or whatever…but you get the idea…
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Alternator mfrs warranty states not more than a 20% phase imbalance - but in reality in use its often way more than that in practice without issues.
But... running at above 50% on one phase & nothing on the other 2 is not a good idea.
Most alternators can be reconfigured to just a dedicated 1ph output if that's what you actually need.
Reconfigured, you have to de-rate the output by one-third (so your 22 would be 14.5-ish)
But... running at above 50% on one phase & nothing on the other 2 is not a good idea.
Most alternators can be reconfigured to just a dedicated 1ph output if that's what you actually need.
Reconfigured, you have to de-rate the output by one-third (so your 22 would be 14.5-ish)
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I installed a robot welder at the Meccalte factory to seam weld the alternator bodies then "stick" the mounting plates on, I say stick because when I asked them about checking the welds I'd just programmed they said "it looks OK", the weld had to support the weight of the alternator hanging under a train
Congrats - their faith must have been justified - cos I've never seen a mounting plate of a Meccalte come unglued from the cylinder/casingI installed a robot welder at the Meccalte factory to seam weld the alternator bodies then "stick" the mounting plates on, I say stick because when I asked them about checking the welds I'd just programmed they said "it looks OK", the weld had to support the weight of the alternator hanging under a train
View attachment 404695
(Mind you - I've never been near one hung under a train)
Guineafowl
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It is indeed. But it’s my mate’s (I look after it), not the OP’s.
We were wandering past it at the Thainstone auctions, looking for a bacon roll. Mate put in an impulse bid.
Got it home - no output. Windings burnt but Perkins engine perfect. Swapped in a new Meccalte alternator and done good service ever since.
not done it yet
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Yep, sorry, my mistake. 5 1/2 kW would be more like it - not 7kW.
Genset mfrs tend to base model numbers on the peak standby rating of the set (which is +10% over the peak continuous rating at variable load).
So the realistic rating of the 22 set is 20kva (16kw), 3-phase.
(Converted to 1ph that 16kw becomes approx. 10.6kW).
Industry standard for 3ph industrial generators is to rate at 0.8pf (lagging).
It's on the basis that the pf of inductive motors is generally around 0.8pf, so the kVA part is the rating running inductive motors (so a motor at 0.8pf run on the genset has the effect that while the alternator experiences the full electrical current/load of the motor, the engine only sees 80% of the mechanical load).
The kW rating is at 1.0pf (or a 1:1 ratio with the KVA) for resistive loads like heating & lighting.
Plus of course - 100kva rating sounds so much more impressive for Sales than 80kW
Basically, whatever the power factor is of whatever the application load is... is what you need to factor in. So if its say an office building its probably 1.0pf (so your 100kva/80kw genny is in this case 80kva/80kw.
Your true baseline is the kw rating as that doesn't change.
So the realistic rating of the 22 set is 20kva (16kw), 3-phase.
(Converted to 1ph that 16kw becomes approx. 10.6kW).
Industry standard for 3ph industrial generators is to rate at 0.8pf (lagging).
It's on the basis that the pf of inductive motors is generally around 0.8pf, so the kVA part is the rating running inductive motors (so a motor at 0.8pf run on the genset has the effect that while the alternator experiences the full electrical current/load of the motor, the engine only sees 80% of the mechanical load).
The kW rating is at 1.0pf (or a 1:1 ratio with the KVA) for resistive loads like heating & lighting.
Plus of course - 100kva rating sounds so much more impressive for Sales than 80kW
Basically, whatever the power factor is of whatever the application load is... is what you need to factor in. So if its say an office building its probably 1.0pf (so your 100kva/80kw genny is in this case 80kva/80kw.
Your true baseline is the kw rating as that doesn't change.
In case ts ever useful.... Meccalte offer upgraded insulation treatments for their alternators (but you have to ask the dealer for it if you want/need it, it cists extra, & there's typically a lead-time implication).
"EG43" is the first upgrade ' like a grey vulcanised/l (epoxy maybe?) extra coating for the stator & exciter stator. This is the one Hire/Rental Co's tend to specify on their hardware.
"Total Plus" is a black coating treatment, and is probably closest to a marine type protection. So if working in very damp, high salinity or similar.
(Nearly all are standard varnish finish. Nothing wrong with it, but like all things it's all about price/cost & being competitive, hence "severe environmental protection" coatings being an option).
