Elektroblock EBL 630B question

[Soarhead]

Hello all, I’m new to the forum and wonder if anyone can answer these two questions?

1. My 2021 Burstner 728G (new to me) is fitted with an Elektroblock EBL 630B power unit located under the passenger seat. The red LED light is flashing on this unit. Does this indicate that the unit is working normally or does it indicate a fault?

2. My fridge works on EHU and gas but not on 12v while driving. There is no power to the terminal block at the fridge but there is power to the D+ connection at the Elektroblock and the batteries charge while driving. It’s not a fuse as I’ve checked them all. I expected to find a 20A fuse for the fridge by the starter battery but there isn’t one. The fuses by the starter battery are 50A and 30A jumbo fused and two standard 10A spade fuses.

It would be helpful to my diagnostics to know if the red LED on this unit is supposed to flash or is it indicating a fault which may explain my fridge issue. The Elektroblock manual just says that there is a LED but it doesn’t explain how it functions! Any informed advice would be appreciated.

 

[StillGoing]

Welcome! Have you read section 6 of the manual about resetting the polyswitch fuses and bus modules?

 

[autorouter]

This EBL 630 is not like most other EBL models. It has a 'bus' system (SDT bus). Power is sent to various 'modules' around the motorhome. Control signals for each module are sent from data connections on the EBL front panel. Each module has a diagnostic LED, maybe you could find them and see if one of them is flashing too.

There are various modules, some specialised, some general. The KM module powers the fridge (= Kuhlschrank Module). If that's not working maybe its diagnostic LED is flashing. I presume the modules are hidden away in hard-to-find places.

 

[Guigsy]

I've got a 630 in my Geist. It's... odd. I did have my control panel die. It meant I couldn't turn on my pump. Don't let your hab battery get too low.

 

[Soarhead]

Autorouter is quite right. I found two separate modules hidden behind a panel in the garage which I believe control the water pump and the water tank sensor. The manual refers to the KM 630 module which controls the fridge but I‘ve torn this van apart and cannot find it!

Welcome! Have you read section 6 of the manual about resetting the polyswitch fuses and bus modules?

StillGoing, thanks for your input. Yes I have read the faults section of the manual which again, doesn't reveal much. I need to find the KM630 module which controls the fridge and can’t understand why Burstner do not locate all of these modules in the same place for easy access. I would still like to find out if the red LED on the Elektroblock is meant to flash once per second in normal operation.

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[Guigsy]

My modules are mostly clustered in a chain near my boiler. But the ones for the tanks are under a panel in a rear locker. I think I've got 6 in total?

The idea is they are located near the item they need to control to minimise wiring complexity.

 

[Newfie]

The flashing red light is normal checked with Schaudt directly when i first saw it on my 630

 

[Guigsy]

The flashing red light is normal checked with Schaudt directly when i first saw it on my 630

I think it's just network activity. Blinkenlights is good... But as I have a fault because my tank sensor is broken, I'm not sure.

 

[Guigsy]

I think it's just network activity. Blinkenlights is good... But as I have a fault because my tank sensor is broken, I'm not sure... And I disconnected the shunt on the battery too. It complains each time I start it. But it does work.

 

[Soarhead]

Many thanks for your replies and to Newfie for confirming that my blinking light is normal. That at least is helpful to my diagnosis. I’m on the road in Portugal but will look closer to the fridge for the KM630 module when I stop for a few days.

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[Guigsy]

My concern with the 630 system is that it's pretty unique. It was only on a few vans for a few years. Not many people understand it. And it's going to be hard to get parts when it breaks.

I think it's a good idea. But I think it's a bit too early for it's time. I'm sure something similar will appear in the future that'll be more widely adopted. But not this time.

 

[autorouter]

Just a suggestion - one possible location for the KM fridge module would be behind the fridge. The fridge power connections and gas burner are normally accessed by removing the lower external vent, so I suppose someone might have thought it was a good idea to put the KM module there too.

 

[Soarhead]

I am making some progress with this issue and have finally found the KM630 fridge module in my Burstner I727G. While I still haven’t solved my problem, what I have discovered may be of benefit to other members of this forum.

Just inside the habitation door is an under floor storage hatch. The inboard section of this hatch is boxed off. It’s under the screwdriver in the first photo below and is secured by 5 torx screws. After removing the screws the cover lifts off to reveal a bunch of modules; KM630; HM631; TM630; and AM632. Two additional Philips screws secure the tray that these modules are affixed to. Removing the screws allows the tray to slide out for better access.

What I found is that each module has a red LED which flashes once a second in sync with the Elektroblock EBL 630 EXCEPT for the KM630 fridge module. There is 12 volts to the connection my finger is pointing at in the photo below, increasing to 13.7 volts with the engine running at idle, yet the fridge will not run on 12 volts.

Now that I’ve found it has anyone any idea what the issue might be?

 

[Newfie]

Try emailing this guy Udo.Lang@schaudt.gmbh & ask very helpful if he if is still working for them

 

[Soarhead]

Thank you Newfie, I will.

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[autorouter]

I don't know this in any great detail, but the general idea of the modules is there is a beefy power supply bus, pos and neg, going down the centre of the modules. There is a 3-wire control bus (SDT Bus) that links all the modules. Commands are sent to the modules along this bus, for example to turn them on and off if the engine starts, or if the user switches the 12V Hab switch on/off. Power and commands to the appliances come from connectors on the side of the modules.

So I think all the fridge connections (Low current control board, high current heater element and engine running signal) come from a connector on the side of that KM module.

One thing I do know is that there are not many standard fuses in the modules, they are mostly polysilicon fuses, which heat up and stop current flowing if there is a fault. To reset them, you have to turn off the power to them for two minutes or more. Maybe you could try some way of resetting them. Perhaps just switch everything completely off for ten minutes or so, but I'm sure there must be a better way.

 

[Peavy]

I would try what autorouter said.
It seems the output in the right side (the one you point your finger at) is working, but the one in the left side (which would be the fridge) doesn't. If the shutdown doesn't work, could be a fault in the KS module.
The idea of a bus system for motorhomes is good, in my opinion, it reduces wiring, I wish it had been explored more to improve it and make it more robust and more reliable for this type of use.

It seems you won't be able to update us in this matter as your five posts as a free member have already been used.