cheesegas

Yep! Should have mentioned that I'm aware the batteries are tired, apologies. Part of the reason of going for the Sterling is that is has alternator temp sensing, although if the Sterling trips on high temp the alternator will still be working fairly hard charging the lithiums through the internal regulator. Building it from Calb cells with a Rec BMS, which has a spare temp sensor which I'm going to configure to disable the B2B from the starter lead-acid if it gets too hot. But that's a discussion for a different topic... I've got just over 1kw of solar, which even on this grey day moored between trees, it's still putting 9a into the batteries so that should keep this old bank happy until I finish the lithium.

I'm seeing 12.2v resting, 13.6v as soon as the engine starts which increases to 14.4v within 1 minute of the Sterling kicking in. It waits for a bit after the engine starts, presumably to avoid belt slippage. Charge current is then 35a. Batteries are probably rather tired, been in the boat since March but they're 4 years old, taken from a project at work after I was done with them! I wouldn't expect them to accept a high current charge to be honest.

Surely the field current controls stator output voltage, so if the Sterling is seeing 14.4v at the batteries it won't increase the field any more? Definitely an A127, and slip rings/brushes are in good order. (not being difficult here, just what I'm thinking!)

Sorry, I should have clarified, yep I know the exciter feed only carries current when the ignition's on and the engine is not running. Started the engine, checked RPM/charge current with a clamp on the alternator cable. Stopped the engine, disconnected the exciter, started the engine. Zero charge current as the alternator's not self exciting, checked RPM.

Also, I've checked alternator RPM with an no contact optical tacho on the pulley, it doesn't change whether it's on/off load which eliminates belt slip. Disconnected the exciter feed from the panel bulb to check. Can't remember the speed offhand but it's around 2500rpm with the engine idling at 1000rpm. Correct me if I'm wrong but the Adverc doesn't kick in until the batteries hit 14v, upon when it cycles between 14v and 14.4v every 15-20 min? Yep, my old 1980 Series III has a 45a A127. Pretty common amongst most BL vehicles I think.

I bought it from a specialist alternator house in London, Unistart, who said it was a refurb unit built to 75a specification by themselves, albeit with a Chinese case. There's very little voltage drop (0.02-0.05v) across the system under load, even when measured from the furthest leisure battery (yep, I know, unequal lengths! Going lithium in the next few months hopefully) as a point of reference, this was the first thing I checked, and much of the wiring is new.

Same, it's all nice new shiny cables on the negative side on clean studs, around 0.02v drop from alternator negative to furthest negative leisure battery. I'm thinking it may not be a 75a regulator.

I've checked that, when I installed the VSR a few months ago I replaced the alternator to starter cable and re-crimped the starter cable ends. It's a short run of chunky 50mm cable, less than 0.05v drop between B+ and starter battery positive when the alternator's working hard. The VSR has a 0.01v drop across it and its cabling to the furthest domestic battery, so that's all fine.

The little LED projectors nowadays are rather good and very efficient. Get one of the brand name ones with a DLP chip, the unbranded Chinese ones are hugely variable in quality and the light source changes colour and drops in output over time. I recommend the Philips ones, the interface is pretty crap but the light source is excellent and DLP gives nice blacks for watching films. Did a lot of research for work, buying over 100 to install into a bunch of brand activations. Buy some high gain front projection screen paint, prime a section of your wall and slap it on. It makes a massive difference. Purpose made pull down projection screens are pretty good too, thanks to the popularity of the mini projectors there’s plenty of boat sized ones on eBay. Avoid plain white paint if possible, you need to make the most of the low lumen output of the projector.

Thanks all. Replaced the diode pack and all works fine now. Voltage ramps up slowly to 14.4 as it did with the old Sterling, and I’m seeing 30-40a charge current when the bank is at 12.2 resting. When the engines running I no longer get the drop in current/voltage when a load is applied. I’m guessing the old Sterling may have killed or damaged the field diodes by forcing the field to full power immediately at every startup, and as I run from solar until fairly late in the year, I didn’t notice the engine wasn’t properly charging while cruising. The solar controller took the voltage to 14.4 whenever I’ve been on the move, having been blessed with lots of sunny days and no shading on the Thames! Now seeing between 1-1.5a field current which is more in line with expectations here. A side note is that the temp sensing isn’t very smart on the Sterling. Unlike other more expensive controllers, it doesn’t lower the field current slowly to find a happy medium, it simply goes 100% hands off until the temp drops. Found out by popping the sensor in a mug of hot water.

Don't know if you've read a Sterling manual, but it's pages and pages of badly written small text with cryptic diagrams in there. At one point, it says the field current will be up to 10a, but the in the specifications of the device a few pages prior, it says a maximum of 13a. Hmm. B+ and D+ voltages are identical.

Thanks for the kind offer but I'm down south in Cheshunt - just ordered a 14v one. A lot of complexity for seemingly no reason! Bought the waterproof version so hopefully the potting compound holds it all where it should be. Yeah, the old one was really badly made and the new ones aren't much better either! No grommets is inexcusable, and it mechanically relies on the solder joint which is crap for something so close to a vibrating engine...

Yep, less than 0.05v difference between any negative point on the system and the batteries. Makes sense. Not sure if the field diodes are in the regulator or the diode pack on the A127 but I'll replace both just in case. As mentioned above, I'll take the field wire to ground and see what happens, will do it when I get back this afternoon. Thanks for the reference on field current too. Thanks for all the help, I'm having trouble replying fast enough! Keep it coming...

13.6v at the batteries and the alternator. It climbs to 14.4v eventually, with or without the Sterling. Thanks. I've never measured the field current with the old Sterling, nor any other one for that matter so I'm not sure what it's supposed to be! 0.5a seems low though. As mine's a neg field alternator I'll take the wire to ground and see if the charge current changes. With reference to ground, the voltage on the field wire with Sterling connected is 6v and disconnected 8v so it's doing something small. Checked the voltage on B+ and batteries, the difference is less than 0.05v. The old Sterling failed because a pair of resistors soldered in a little arch where there's room for just one on the PCB fell off. No idea on the value as said resistors are probably somewhere in the bilge... The new Pro Reg D (not the waterproof one) has got all the LEDs on a mezzanine PCB which is asking for the same thing to happen with vibration!

Yep, that's my thoughts that the alternator regulator is dodgy. I replaced the entire alternator less than 6 months ago due to a bad bearing but it could still be bad. The field wire is what Sterling refer to as the 'field control wire' which comes from the regulator and is connected to one of the alternator brushes; in the case of my neg field control alternator, it should be sinking current into the regulator to raise the field voltage. Sense wires are all correct, I replaced it all with the new regulator just in case. I'm seeing no drop when measuring voltage between the battery and regulator sense wire. The 10a is quoted from the manual, it says it can be as high as 13a which I agree is high. Thanks. Confident that all connections are good and clean as I replaced it all when I fitted the VSR a few months ago. Isolator switches and battery terminal clamps are also brand new, and I'm not seeing any voltage drop across any components in the system. Measuring between battery positive post and any other point in the system doesn't show any voltage drop either. Agreed on the diodes, although why it initially charges at high current before immediately dropping has me stumped. I'm going to fit a new alternator regulator and diode pack I think. What doesn't make sense in my statements?

Hi all. Got a weird alternator issue, I'm pretty clued up on electrics but this is weird! Setup is an Isuzu 3KC1 (idles at 1000rpm as per the engine manual), single alternator V belt drive (tensioned, no slipping), 75a Lucas A127 clone (negative field control) connected to the starter battery, three 110ah leisure bank, one 110ah starter, Sterling VSR set to 13.6v, Victron BMV on the leisure bank with start batt monitoring. Originally there was a very old but functioning Sterling alternator regulator fitted. This worked great, slowly ramping up the voltage to 14.4v within 20 min of starting the engine. Charging a depleted bank resting at 12.2v, I'd see around 30a charge current for half an hour or so before tailing off as expected. However the regulator recently failed closed, meaning the voltage would rise up to over 15v within minutes of starting the engine, and then the regulator's relay would open when it trips on high voltage, leaving the alternator's internal regulator to work. I removed the old Sterling and have been using the internal regulator for a while - on startup, I'd see 15-20a charge current at 13.6v, current decreasing as voltage increases as normal. However, putting a load of around 25a on the battery with the engine running and a charge current of 10a would instantly pull the voltage down, and a current of around 10a would flow from the batteries. Made me have doubts about the alternator's regulator. Anyway, yesterday I finally got round to fitting a new Sterling Pro Reg D. Checked the ignition feed, replaced the 12v battery sense and all grounds to the Sterling, checked that I'm seeing 6-8v from the field wire on the alternator. Fitted the regulator and I'm seeing absolutely no change in the above behaviour! No error lights on the regulator and it's in high charge mode. It also does not ramp up the charge voltage at all; after 2hrs of engine running, the voltage is still the same as if the internal regulator is being used. I've tried the below: - Disconnecting the field wire from regulator to alternator does nothing at all, no change to voltage or charge current. - There's a 0.5a current flowing in the field wire. Sterling manual says this should be around 10a? - All grounds have under 0.05v potential difference between them; alternator, both battery banks, sense wires for the Sterling (both battery and alternator ground sensing) - All 12v points have under 0.05v difference between them; alternator, both battery banks, sense wire for the Sterling - Sterling is set to negative field control The new Sterling is currently connected. The batteries got quite low last night as I had the inverter on, 12.1v rested so they should be accepting a high charge current. Started the engine this morning and the charge current went up to 25a at 13.6v relatively quickly which is what I'd usually expect, then after less than a minute it dropped to 10a. When the fridge kicks in, charge current drops to 6a at 13.6v. Is this is a stuffed alternator internal regulator? And a DOA Sterling? The Sterling appears to be doing precisely nothing, the white field wire is not sinking any significant current from the field winding even though the lights on the front say it's all happy. Thanks for your help!

OP, Aldi have a surprisingly decent one at the moment for only £9.99, go have a look if they have any left. Really handy for fault finding anything electrical on a boat, there's plenty of tutorials on youtube on how to use one to measure voltage and continuity.

Their site isn't very good, you need to go into the Products page, select a pump and then click Downloads to get the spec sheet. Looks like it's around 7-10 amps depending on backpressure. https://daviescraig.com.au/media/694/1427092566.EWPSelectionGuideTechSpecs2009.pdf

The litres per minute assumes that there's no restriction on the output - depending on the pump, the flow will drop in different proportion to the pressure. Davies Craig publish theirs, can you compare it against your current pump? https://daviescraig.com.au/electric-water-pumps near the bottom. I've got a feeling the flow rate of the existing intercooler pump isn't much under pressure.

The other problem is that it won't be continuously rated, and uses a brushless motor so the service life will probably be in the hundreds of hours. Lots of cars use electric water pumps now, to supplement the engine driven one for intercooler or heater circuits. They're not cheap but are brushless, high flow and have a long service life as there's no mechanical seal on the shaft between pump and motor - it's magnetically driven. Most common one is the Bosch PAD12V but there's plenty of other options with higher flow and different output spigot sizes. As the pump has a built-in RPM sensor similar to brushless motors in computer fans, it can be used with a compatible controller to give a low RPM alarm...and the fancier controllers can also ramp up/down the pump speed at specific temperatures or run it on a timer after the engine's been turned off.

It's also worth noting that if you have a 2kw kettle which you switch on while running the engine, unless you have a massive alternator it will not be able to keep up with the 170 or so amps required. The batteries will make up the difference, and drawing sustained high currents from lead-acids isn't very efficient. They'll need to charge - slowly - after each kettle is boiled. However, a 750w kettle will need around 70 amps, most of which the alternator will be able to supply.

Take a closer look at the key - it's not a simple rack and pinion in there, with a universal key. The keys go into a four sided barrel with one set of tumblers and pins, so just like a normal Yale lock, using a screwdriver to turn the barrel doesn't work because the pins are in the shear line. There's a few million key differs with this design too. The mechanism also deadlocks the bolt so it can't simply be pushed back in. I have them on my front door and can confirm that just like a regular lock, turning the barrel with a screwdriver does sweet nothing.

I've always wondered this too. Silenced 10-20kva generators often have similar sized diesel engines, cocooned in a box barely bigger than the engine and are radiator/forced air cooled. They have to deal with cooling a bloody great alternator too, at full output at 1500rpm continuously. Guessing it's because you'd need a fairly big vent for the intake/exhaust air, which takes up a lot of space on a narrowboat and is difficult to duct into a cruiser stern. The radiator is also quite big and flat which is hard to hide on a small boat. Without baffling, the fans can be loud, and would need to be electric rather than engine driven due to the location. Adding complexity, you could even have a couple of smaller radiators, one each side on a trad stern but you'd have to have vents on the outside and would lose internal space.

The 501 is very old, and I don't think it speaks ve.direct as it has an RJ-11 port, so the ve.direct to USB kits won't work. I think the original PC interface kit converted to RS232 only, to give you some idea! There's no documentation available on the protocol so unless you happen to find the interface kit on ebay, you'd need to do some serious reverse engineering to find out what data it's spitting out. Chances are it's RS232/RS485 at a non standard voltage level... You'd be better off getting a Smart Shunt and a ve.direct to USB cable. I use a 712 with a ve.direct to USB with a RPi 3+ and it works very well.

It's worth investing in a decent battery meter which can measure current going in and out anyway - voltage only gives you half the story, as it will sag under load and recover. Likewise, if you charge a heavily depleted bank for an hour, the resting voltage after a few minutes will appear like it's fully charged. However, you're just seeing the surface charge on the plates and the batteries in reality aren't charged. Victron's BMV series and Smart Shunt (same thing but minus a screen) have data ports which can be connected to the Pi via a USB converter, and the ve.direct protocol is largely open source. The BMV pushes almost every parameter over ve.direct once per second, so you can harvest and log all the data you want on the Pi...current, voltage, state of charge, amp-hours consumed, starter battery voltage. The Smart versions have Bluetooth which is remarkably good, on a 45' boat it'll reach all the way to the front deck if mounted in a cupboard in the back. https://www.victronenergy.com/battery-monitors/smart-battery-shunt https://www.victronenergy.com/battery-monitors/bmv-712-smart