- Thread starter Justme
- Start date
Hello all,
it's worth a check of the diodes in the exciter, if they are gone there will be no field current and hence no or little generation. A simple multimeter will do, should show continuity one way but change the probes over should show very high resistance, basically no movement of the needle on low ohms. It will probably be necessary to disconnect the diode so as not to test with a parallel path which will give a false reading.
Alec
Alec
it's worth a check of the diodes in the exciter, if they are gone there will be no field current and hence no or little generation. A simple multimeter will do, should show continuity one way but change the probes over should show very high resistance, basically no movement of the needle on low ohms. It will probably be necessary to disconnect the diode so as not to test with a parallel path which will give a false reading.
Alec
Alec
Good point. I did check that the valve moved freely by hand (spring pressure is quite low so you can push it down with fingers) but it was a cold engine then.
I think there are ok as I am getting correct voltage / current control now. Even at low loads its producing correct volts & powering the inverter charger fully.
Oddly the engine seems to be stopping every 90mins. I am wondering if the auto run system (which I use to remote start the genny either personaly or via a control that monitors the batty state of charge) has a timer built into it. But it dint used to do that so if so I must have activated it whilst putting it back together.
Justme
jugs
Dont wish to offend & annoy, but...
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Sounds like spring is too soft ,thats why cap jumped off. The valve gear is moving faster than the valve, try a new spring
On a car I would think you are right. Remember this is only a small engine running at less than half the (fixed) revs of a car. The exhaust is about the same. I would say its about half the spring pressure of your average car valve spring. But that said I will keep it in mind & if I need to strip it down again if they are available I will fit them.
Has stopped again (and again) every 90mins. Its got to be a timer some place.
Justme
Has stopped again (and again) every 90mins. Its got to be a timer some place.
Justme
Hi thanks to Piman, I have had another look at my generator, I am not really into electrics and can struggle with a multi meater, but hear goes. Small diode on a circuit board did the check with my meter and current flows one way but not the other, assuming that is OK.
There is a square block on the back of the plug panel board, has 4 terminals on it and the earth connection on the front. I googled the part number and it is a Bridge Rectifier part number KBPC3510, and it appears to be some sort of diode. Lots for sale on the net, for £2-£3 so hardly an expensive component. I did the same checks to this as the diode on the circuit board, and testing all 4 terminals both ways revealed that currant flowed one way but not the other, so I think it may be OK.
Of the 4 wires to the bridge rectifier, 2 are red, 2 are black. 1 red one goes to the alternator and one black one goes to the alternator though a reset switch ( have checked switch and it is OK). I have also checked the continuity of these wires, and there is no resistance. The other 2 (red & black) go to two 12volt pickup points and then back to a circuit board which I think is to do with starting and charging the generator engine, but I do assume that there must be a 12volt feed from here to go into the bridge rectifier and then into the alternator to excite/generate electricity, but I am not sure.
There are 4 wires from the alternator and they are in 2 pairs, L1 & L2. And R1 & R2, I have checked the continuity of these wires in there pairs with the meter set to 20k, and there is no resistance ether way. Not sure what I should get though. L1 and R1 go to a consumer unit stile circuit breaker, and then to a switch that selects 110v or 230v, L2 and R2 go to straight to this switch. The output of this switch goes to additional circuit breaker for 110v and 230v and finally the plugs.
There is a capacitor on the back of the alternator attached to 2 wires that come from the windings, I have checked these wires for continuity and they show no resistance. I have checked the capacitor by putting the meter to it and then swapping the terminals around and the reading fluctuates down to zero each time. I did change this capacitor for a new one as I was told it was the most likely cause of my trouble, but no change. Capacitor is a 14uf +-5% 450v.
If all the above figures/tests I have done, are correct. Is it likely to be a problem with the supply to the bridge rectifier? There is also a large aluminium lump with 3 wires and cooling fins, this is connected to the 12v side, looks a bit like a voltage regulator of some sort, but I don’t know.
I realise the above may not make sense, but as I said I am strong on electronics. Any help or advice as what to do next would be greatly appreciated. A generator that doesn’t make electricity is not much use.
There is a square block on the back of the plug panel board, has 4 terminals on it and the earth connection on the front. I googled the part number and it is a Bridge Rectifier part number KBPC3510, and it appears to be some sort of diode. Lots for sale on the net, for £2-£3 so hardly an expensive component. I did the same checks to this as the diode on the circuit board, and testing all 4 terminals both ways revealed that currant flowed one way but not the other, so I think it may be OK.
Of the 4 wires to the bridge rectifier, 2 are red, 2 are black. 1 red one goes to the alternator and one black one goes to the alternator though a reset switch ( have checked switch and it is OK). I have also checked the continuity of these wires, and there is no resistance. The other 2 (red & black) go to two 12volt pickup points and then back to a circuit board which I think is to do with starting and charging the generator engine, but I do assume that there must be a 12volt feed from here to go into the bridge rectifier and then into the alternator to excite/generate electricity, but I am not sure.
There are 4 wires from the alternator and they are in 2 pairs, L1 & L2. And R1 & R2, I have checked the continuity of these wires in there pairs with the meter set to 20k, and there is no resistance ether way. Not sure what I should get though. L1 and R1 go to a consumer unit stile circuit breaker, and then to a switch that selects 110v or 230v, L2 and R2 go to straight to this switch. The output of this switch goes to additional circuit breaker for 110v and 230v and finally the plugs.
There is a capacitor on the back of the alternator attached to 2 wires that come from the windings, I have checked these wires for continuity and they show no resistance. I have checked the capacitor by putting the meter to it and then swapping the terminals around and the reading fluctuates down to zero each time. I did change this capacitor for a new one as I was told it was the most likely cause of my trouble, but no change. Capacitor is a 14uf +-5% 450v.
If all the above figures/tests I have done, are correct. Is it likely to be a problem with the supply to the bridge rectifier? There is also a large aluminium lump with 3 wires and cooling fins, this is connected to the 12v side, looks a bit like a voltage regulator of some sort, but I don’t know.
I realise the above may not make sense, but as I said I am strong on electronics. Any help or advice as what to do next would be greatly appreciated. A generator that doesn’t make electricity is not much use.
The ali lump is for 12v charging.
The L1 L2 R1 R2 need testing with all the cables removed (make sure you mark them first). The L's shouls be connected & the R's but no connection between L & R.
It could be that you have lost the residual magnetisum.
Sounds like all the diodes are ok
You description sounds like mine apart from the cap value.
Justme
The L1 L2 R1 R2 need testing with all the cables removed (make sure you mark them first). The L's shouls be connected & the R's but no connection between L & R.
It could be that you have lost the residual magnetisum.
Sounds like all the diodes are ok
You description sounds like mine apart from the cap value.
Justme
I would check the windings with a insulation tester. It applies 250 volts to the circuit under test, better then using just a normal multimeter. Most electricians will have one of these.
You can't really test capacitors, only find out if they are shorted internally or not.
If the windings are ok its a voltage regulator fault.
There isn't much else to go wrong.
You can't really test capacitors, only find out if they are shorted internally or not.
If the windings are ok its a voltage regulator fault.
There isn't much else to go wrong.
Hello Howburn,
the diodes I was referring to were exciter diodes, often they screw into the generator shaft.
Basically a brushless alternator has two generators, the exciter which generates the field voltage and the AVR controls the field voltage in response to demand on the machine. The main generator is what gives the mains voltage output, and is the largest part of the stator.
Alec
the diodes I was referring to were exciter diodes, often they screw into the generator shaft.
Basically a brushless alternator has two generators, the exciter which generates the field voltage and the AVR controls the field voltage in response to demand on the machine. The main generator is what gives the mains voltage output, and is the largest part of the stator.
Alec
Thanks for the comments.
The genny is a Pramac P6000s.
Lovely & quiet. Runs smooth starts on the button every time.
Has some good design features (like the oil drain pipe, Fuel filler & level indicator, single lifting hook, elec & pull start, not that its been needed yet). The wheel kit is ok but does add to the noise so needs a bit of padding to stop handle shaking.
I would highly recommend the genny, but so far cant recommend the UK agent. The dealer (Just Generators) has been ok too.
(had it failed out side the warrranty I would have done more tests on it my self & would have found the fault & fixed it for less than a tenner & if I could not find it a local genny place would have done it for a reasonable fee, in fact last time I have work done (sorting out the elec motor on a hydraulic sausage stuffer) I paid him in fresh meat from our own on farm butchers shop)
I want to add remote start & stop to it (but not auto mains fail start) so in winter I dont have to go outside in the rain to opperate it & I also have a bat SOC (thats state of charge) meter that can activate a set of contacts at a pre programmed V or SOC to trigger the remote start & then hold it till the bats are full & had an EQ charge.
I can also do the same with the inverter & solar charge controller as they too have controllable relays.
I had a genny before this one that had auto start on mains fail. I just used the on & off switch on that to trigger it as the mains was not passed through the ports just turning it on would start the genny. In fact I still have it but would need to sort the wiring out to add it to this one.
Service oil change is in the book at 200 hours I have been doing it at 100.
It runs for between 6 & 12 hours every 3 to four days. So about 12-20 hours per week max.
Just checked that & my usage this year has been
Month Hours
JAN 88
FEB 80
MAR 88
APR 86
MAY 88
Had less solar panels in Jan to May as I added 50% more in Jun/Jul
JUN 33 (just for power tools)
JUL 0 KWh made from genny (only started recording from here)
AUG 25 24 (just for power tools)
SEP 29 56
OCT 65 113
NOV 68 112
DEC ?
June July & Aug was mainly running it for power tools.
I check the oil every time I start it. When new it used lots of oil for the first 50 odd hours & then slowed down & is now hardly using any.
We dont use it much in spring & summer as the solar will provide nearly all our needs. Just the odd day running power tools ect.
Our standard max load is less than 4000w with every thing on & the longer its on the more it goes down due to the bats taking less from the charger. The biggest single load would be my welder. But that only ever used on its own at low settings & is plugged in via the 15amp breaker so cant draw more than 3600watts ish & I dont use it often. I am however looking at a bigger genny (poss PTO as its more mobile & can be used as a back up if the main one fails again) for it as I cant turn it up to max for thick stuff.
They have point blank refused to do it under warranty. Even after my selling dealer tried to convince them. The dealer has just passed on the costs with no mark up.
The repair bill is
courier both ways £90.70 (which is cheap for a 200kg plus pallet on next day)
capacitor £4.50
Labour £54.67 (just to test & fit cap)
VAT £19.14 (already added in above costs)
Total £146.75
(the thing is I would have been liable for the courier any way & had it been a warranty item I would have had the dealer service as well, so all it would have cost them is the £4.50 cap & 30 seconds to fit it)
Thats the min to fix.
They also wanted to do a service for about £100 but I said no.
So they would have got more money out of me doing it as a warranty item.
But I did buy a service kit for £37.63 inc vat that contains
1x air filter
1x oil filter
1x gauze fuel filter
1x paper fuel filter
2 x 1 litre bottles of oil
(did try to not have the oil as I buy that in bulk but its part of the "pack")
The thing is that they have now fixed it (due back on Monday) & I assume tested it WITHOUT DOING THE SERVICE that they say caused the failure.
It will be interesting to measure the RPM when it returns to see if it really is slow & if it changes after fitting the new filters.
I can even if needed set the inverter to Assist Mode. So if the power need hits the limit set for the available power from the genny (which I set for 1 or 2 amps below max) it will sync with the genny & add in the extra power needed. It also has a UPS mode where the switching is extra fast (but the standard setting does it quick enough for tv, lights & computers any way)
At the min I am borrowing a cheapy import petrol 2000w genny. Its coping with all our standard loads apart from the inverter drops the charging when the freezer starts (due to hertz going down to 47/48, at 52 off load), but once started it starts charging again so is coping with the load just not the starting load.
With luck it will be back later today.
The genny is a Pramac P6000s.
Lovely & quiet. Runs smooth starts on the button every time.
Has some good design features (like the oil drain pipe, Fuel filler & level indicator, single lifting hook, elec & pull start, not that its been needed yet). The wheel kit is ok but does add to the noise so needs a bit of padding to stop handle shaking.
I would highly recommend the genny, but so far cant recommend the UK agent. The dealer (Just Generators) has been ok too.
(had it failed out side the warrranty I would have done more tests on it my self & would have found the fault & fixed it for less than a tenner & if I could not find it a local genny place would have done it for a reasonable fee, in fact last time I have work done (sorting out the elec motor on a hydraulic sausage stuffer) I paid him in fresh meat from our own on farm butchers shop)
I want to add remote start & stop to it (but not auto mains fail start) so in winter I dont have to go outside in the rain to opperate it & I also have a bat SOC (thats state of charge) meter that can activate a set of contacts at a pre programmed V or SOC to trigger the remote start & then hold it till the bats are full & had an EQ charge.
I can also do the same with the inverter & solar charge controller as they too have controllable relays.
I had a genny before this one that had auto start on mains fail. I just used the on & off switch on that to trigger it as the mains was not passed through the ports just turning it on would start the genny. In fact I still have it but would need to sort the wiring out to add it to this one.
Service oil change is in the book at 200 hours I have been doing it at 100.
It runs for between 6 & 12 hours every 3 to four days. So about 12-20 hours per week max.
Just checked that & my usage this year has been
Month Hours
JAN 88
FEB 80
MAR 88
APR 86
MAY 88
Had less solar panels in Jan to May as I added 50% more in Jun/Jul
JUN 33 (just for power tools)
JUL 0 KWh made from genny (only started recording from here)
AUG 25 24 (just for power tools)
SEP 29 56
OCT 65 113
NOV 68 112
DEC ?
June July & Aug was mainly running it for power tools.
I check the oil every time I start it. When new it used lots of oil for the first 50 odd hours & then slowed down & is now hardly using any.
We dont use it much in spring & summer as the solar will provide nearly all our needs. Just the odd day running power tools ect.
Our standard max load is less than 4000w with every thing on & the longer its on the more it goes down due to the bats taking less from the charger. The biggest single load would be my welder. But that only ever used on its own at low settings & is plugged in via the 15amp breaker so cant draw more than 3600watts ish & I dont use it often. I am however looking at a bigger genny (poss PTO as its more mobile & can be used as a back up if the main one fails again) for it as I cant turn it up to max for thick stuff.
They have point blank refused to do it under warranty. Even after my selling dealer tried to convince them. The dealer has just passed on the costs with no mark up.
The repair bill is
courier both ways £90.70 (which is cheap for a 200kg plus pallet on next day)
capacitor £4.50
Labour £54.67 (just to test & fit cap)
VAT £19.14 (already added in above costs)
Total £146.75
(the thing is I would have been liable for the courier any way & had it been a warranty item I would have had the dealer service as well, so all it would have cost them is the £4.50 cap & 30 seconds to fit it)
Thats the min to fix.
They also wanted to do a service for about £100 but I said no.
So they would have got more money out of me doing it as a warranty item.
But I did buy a service kit for £37.63 inc vat that contains
1x air filter
1x oil filter
1x gauze fuel filter
1x paper fuel filter
2 x 1 litre bottles of oil
(did try to not have the oil as I buy that in bulk but its part of the "pack")
The thing is that they have now fixed it (due back on Monday) & I assume tested it WITHOUT DOING THE SERVICE that they say caused the failure.
It will be interesting to measure the RPM when it returns to see if it really is slow & if it changes after fitting the new filters.
I can even if needed set the inverter to Assist Mode. So if the power need hits the limit set for the available power from the genny (which I set for 1 or 2 amps below max) it will sync with the genny & add in the extra power needed. It also has a UPS mode where the switching is extra fast (but the standard setting does it quick enough for tv, lights & computers any way)
At the min I am borrowing a cheapy import petrol 2000w genny. Its coping with all our standard loads apart from the inverter drops the charging when the freezer starts (due to hertz going down to 47/48, at 52 off load), but once started it starts charging again so is coping with the load just not the starting load.
With luck it will be back later today.
Well its arrived back.
So I refilled it with oil & started her up. Was running smooth (remember this is with no load & before the service).
I then connected it up to my system to see what it was doing with a very small load & a larger load.
I then fitted the service parts & repeated the test.
I was hoping to be able to show a difference in the before & the after shots but they were the SAME.
This is small load
This is a larger load
UMains = incoming mains voltage
IMain = incoming current
UOut = voltage entering the domestic meter
IOut = current being used via the domestic meter
Udc = battery bank voltage
Udc = ripple is battery bank voltage variation
Idc = charging current going into the battery bank
Freq Out = Hertz at domestic meter
Freq In = hertz from genny
The first pic shows a 0.3 amp load on mains & no charger (the other 0.1 amp is the system load) so 0.4amps from genny.
The second pic shows a 9 amp total load on genny with the same 0.3 amps to the mains meter & the charger using the rest to charge at 106 amps.
As you can see the herts (so engine speed) is high at 54 hertz with virtually no load & still slightly high at 52 hertz with the largest load we can apply.
It is also interesting to see that the £200 AVR module seems to not be working very well as the genny voltage alters from 226v no load to 219v under half load.
So I refilled it with oil & started her up. Was running smooth (remember this is with no load & before the service).
I then connected it up to my system to see what it was doing with a very small load & a larger load.
I then fitted the service parts & repeated the test.
I was hoping to be able to show a difference in the before & the after shots but they were the SAME.
This is small load
This is a larger load
UMains = incoming mains voltage
IMain = incoming current
UOut = voltage entering the domestic meter
IOut = current being used via the domestic meter
Udc = battery bank voltage
Udc = ripple is battery bank voltage variation
Idc = charging current going into the battery bank
Freq Out = Hertz at domestic meter
Freq In = hertz from genny
The first pic shows a 0.3 amp load on mains & no charger (the other 0.1 amp is the system load) so 0.4amps from genny.
The second pic shows a 9 amp total load on genny with the same 0.3 amps to the mains meter & the charger using the rest to charge at 106 amps.
As you can see the herts (so engine speed) is high at 54 hertz with virtually no load & still slightly high at 52 hertz with the largest load we can apply.
It is also interesting to see that the £200 AVR module seems to not be working very well as the genny voltage alters from 226v no load to 219v under half load.
