MiketheBike Posted October 9, 2009 Share Posted October 9, 2009 (edited) I just started the Ferret, the first time in maybe a month. I put two new batteries in, as the originals were stuffed. I checked the charging voltage at tickover at the accessory socket, and it read 32V, it goes up to about 33V at higher revs...is that OK or is it going to fry the batteries. Should I check the voltage at the batteries instead? Do you think that is due to having to crank it over for maybe 30 or 40 seconds to get the fuel up and get it it started (I cranked it over in 10 second bursts...not a full 30 seconds in one go). It starts and runs fine. Mick Edited October 9, 2009 by MiketheBike Quote Link to comment Share on other sites More sharing options...
fv1609 Posted October 9, 2009 Share Posted October 9, 2009 Mick it's far too high. Maybe that was what stuffed the other batteries? Do you have Generator No. 2 (ie 2-speed 25A) or Generator No.10 (90A)? Quote Link to comment Share on other sites More sharing options...
MiketheBike Posted October 9, 2009 Author Share Posted October 9, 2009 Hi Clive, its a number10, mk2 Mick Quote Link to comment Share on other sites More sharing options...
fv1609 Posted October 9, 2009 Share Posted October 9, 2009 (edited) Right well you will have the Gen Panel No.9 probably Mk 2 or Mk 3. I doubt that it would be the Mk 4. I would just take a voltage reading directly on the batteries to make absolutely certain what you are dealing with. Assuming it is NOT a Mk 4 then take the lid off & flick the contacts on the vibrating contact voltage regulator as this controls the voltage to the field winding that dictates the output from the alternator. This should be buzzing & slightly sparking at the contacts. Might be worth very gently rubbing very fine abrasive paper & wiping it clean of dust & grot. If having done that it still gives too much output, then as an emergency measure you can change the voltage setting link to the LOW position. This was for use in the tropics where ambient heat & that of the charging system caused the acid to gas. Edited October 9, 2009 by fv1609 Quote Link to comment Share on other sites More sharing options...
MiketheBike Posted October 9, 2009 Author Share Posted October 9, 2009 Thanks Clive You never cease to amaze me I will have a look first thing tomorrow. Is this kinda common then and would dirty contacts cause voltage increase? Sounds like if you leave electrical contacts unused for a long time they would oxidise and cause this, or do they self clean because they spark? Mick Quote Link to comment Share on other sites More sharing options...
fv1609 Posted October 9, 2009 Share Posted October 9, 2009 Is this kinda common then and would dirty contacts cause voltage increase? Sounds like if you leave electrical contacts unused for a long time they would oxidise and cause this, Yes I've had it happen. Often it is not as dry & clean as you think in there, not unusual to see corrosion on some components at least. Mine was pushing out 32v & destroyed a pair of batteries after a couple of seasons. I was reassured as it seemed to be so good at charging! I fitted a brand new panel that was still sealed in its box & that didn't work at all! I plugged in several that I had lying around. The best regulation came from a muddy & battered one that was on the ground at a scrapyard & that was perfect inside! Quote Link to comment Share on other sites More sharing options...
MiketheBike Posted October 9, 2009 Author Share Posted October 9, 2009 Clive, now I'm a bit confused (not difficult). I have looked at the Ferret user handbook (12174) , and the tech handbook (V622) and can only find the No2 panel...and that looks nothing like mine, so I guess the No9 was a later one? It has a large relay on the right, that closes when you release the starter and the engine is running, and that does not appear to be in the pictures of the No2. When I went out and started it up, there was still 32V. I stopped the engine, took off the cover and restarted...it now read between 28.2V and 28.8V dependant on revs. Put it all back together and it remains charging at that voltage. It looks very clean and good condition, maybe I should roll it in some mud I still want to give the contacts a clean as you suggest, but could not see anything oscillating or sparking. What do the contacts look like (I didn't think to take a photo as it started to rain, but could do that tomorrow. Cheers Mick Quote Link to comment Share on other sites More sharing options...
fv1609 Posted October 9, 2009 Share Posted October 9, 2009 (edited) Mick ignore the User Handbook! There was a programme to upgrade Saracens & Ferrets to the 90A system used in Land Rovers. That is what you have. This programme started in 1978 but abandoned after they ran out of components. If you have a white rubbery thing inside the panel that is the transistorised version ie Mk 4 & you cannot adjust it other than the HIGH/LOW option. If you have an earlier panel the regulator is near the HIGH/LOW switch in the compartment that the main relay is housed. It could be that the regulator contacts are stuck together & it is delivering max charge all the time. Edited October 9, 2009 by fv1609 Quote Link to comment Share on other sites More sharing options...
MiketheBike Posted October 10, 2009 Author Share Posted October 10, 2009 (edited) Thanks Clive, I had another look today, and it still seems to charge at around 28 - 29V. Do you think that is an OK range? The contacts you mention, are they the ones on the left, just below the High/Low switch, having "C.A.V." marked on them? There are two screws marked with yellow paint, are the contacts behind those? Are the screws to adjust the charge voltage? Cheers Mick Edited October 10, 2009 by MiketheBike Quote Link to comment Share on other sites More sharing options...
fv1609 Posted October 10, 2009 Share Posted October 10, 2009 Thanks Clive, I had another look today, and it still seems to charge at around 28 - 29V. Do you think that is an OK range? Yes The contacts you mention, are they the ones on the left, just below the High/Low switch, having "C.A.V." marked on them? Yes What happened to the 33 volts? But if its 28-29v then that's fine leave it alone. But you should witness a buzzing & slight sparking from the regulator as it does its job. The big BCK relay on the lower right is energised by an independent output from the alternator. When that rises to the required voltage the radio & vehicle batteries are put in parallel & also are connected to the main output from the alternator. You can see the reason for insulating the radio batteries leads from each other & the chassis if you have no radio batterries connected! Quote Link to comment Share on other sites More sharing options...
fv1609 Posted October 11, 2009 Share Posted October 11, 2009 Mick it looks to be spot on now. Here is part of the Inspection Standard for the Mk3 panel from EMER POWER P 138/27 Part 2. You will see how the output voltage remains constant for loads of 10, 66 & 88 amps. But note how the revs have to understandably increase to realise full power out. Battery relay LH column = Base Standard RH column = Field Standard Quote Link to comment Share on other sites More sharing options...
MiketheBike Posted October 11, 2009 Author Share Posted October 11, 2009 Clive, I am not sure what happened to the 33V. It was running at that until I took the lid off the panel, maybe knocking the panel about did something? I can see what you mean about the relay down on the right. I started her up and the engine was running really slow (ignition light was still on), but as soon as I touched the accelerator and the ignition light went out, that relay operated. I did give the contacts on that part marked CAV a ping as you suggested, but I still cannot see any sparking, although that may be my eyes I will definitely have to keep an eye on the voltage for a while to make sure it does not increase like that. I am still wondering if its because it was left for a while and just needed to be run the clean the contacts. Thanks Again Clive Mick Quote Link to comment Share on other sites More sharing options...
fv1609 Posted October 11, 2009 Share Posted October 11, 2009 Mick, I suspect the regulator contacts were stuck closed & giving the field winding too much voltage. The sparking at the contacts will be minimal if they are clean & in good condition. But you should be able to feel a slight buzz as you touch the regulator (as in a vibrating contact regulator). Be very careful as although it is low voltage, you can sometimes get a shock where inductive loads are around. Yes it is a good idea to run everything up every few weeks, at least with this later generator you don't have to pour oil into the dynamo bearings like on the original fit dynamo. Quote Link to comment Share on other sites More sharing options...
MiketheBike Posted October 12, 2009 Author Share Posted October 12, 2009 ok...now that you say I may get a shock I am afraid to touch them! Maybe I will get the kids to check if its buzzing, I'll get them to eat a bag of crisps first...the salt should make it more fun Quote Link to comment Share on other sites More sharing options...
MiketheBike Posted October 15, 2009 Author Share Posted October 15, 2009 Well...it does seem to be buzzing...and the voltage has remained inside the 28 - 29V range, so I think you are right, the contacts may have been stuck is this the same cable as that in the Ferret? http://cgi.ebay.co.uk/Land-Rover-Military-Series-3-FFR-Generator-Cable_W0QQitemZ270467480242QQcmdZViewItemQQptZUK_CarsParts_Vehicles_CarParts_SM?hash=item3ef91e3ab2&_trksid=p3286.c0.m14#ht_500wt_927 He is also selling a generator panel, #9 mk4 from a landrover 109, so thought this cable may the the correct type and length? The cable I have at the moment is not in very good condition. Quote Link to comment Share on other sites More sharing options...
fv1609 Posted October 15, 2009 Share Posted October 15, 2009 (edited) is this the same cable as that in the Ferret? I don't know, but I think electrically it would be ok. Ask him to measure it & compare with yours. Is it shorter than this one? As far as the Gen Panel No.9 Mk4 goes I'm not familiar with the Ferret layout, do you have any ammeters? The Mk3 & earlier panels were intended to be used with a separate shunt box & 2 ammeters on the dash of the Land Rover (one for vehicle batteries & the other for radio batteries) When the Mk4 came along it was used in installations that had a single radio ammeter built into the shunt box. Both types of Gen Panel will work on your installation. (If you used a Mk3 panel on a Mk4 installation, the charge light would not work although it would still charge). With the Mk4 panel there is a transistorised regulator, it cannot be revived by cleaning any contacts! Edited October 15, 2009 by fv1609 Quote Link to comment Share on other sites More sharing options...
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