Battery Masters and Connection to rear of EBLs (1 Viewer)

[dathers]

Hi quick question, following on a slightly different thread from my post the other day.

If I decide to go belt and braces and add a battery master, on top of a dual charging solar reg, I believe the best way to connect is via the back of the EBL (mines and EBL 101). However space is really tight for me and I'm not sure splicing into the existing three cables would be a good idea, just wondered if anyone else has done this and if they had any pics and or advice.

Thanks Dave

 

[Zigisla]

Not sure the difference my 119 is, but this is how my bm is set up. Red and Black to the solar connection and the Brown soldered into the main charger cable.

 

[dathers]

Thanks , great picture, thats the second one I've seen like this and I know from the other report it works great but my solar block is used on my 101, but there is a spare slot to the side which is labelled for an additional charger which I may be able to use but not sure.

Wish I understood some of the electronics - If BM works on sensing a voltage drop from the starter battery and then redistributes power from the leisures to the starter my simple brain struggles to compute this, how does it know the starter is low?

^{_{Subscribers  do not see these advertisements}}

 

[eddie]

It measures the voltage

 

[autorouter]

Because you have an EBL101, you could have used the solar charger input for all three Batterymaster connections. @Zigisla didn't do that because the EBL119 is slightly different, and the centre pin of the solar input doesn't go straight to the starter battery. Of course because you intend to use the solar charger plug for a genuine solar charger, that option is out anyway.

You could splice all three into the solar charger connector. That would be easier than trying to splice into the thick cables at the back of the EBL

there is a spare slot to the side which is labelled for an additional charger which I may be able to use but not sure.

There is a simple alternative for two of the connections. The 'Additional Charger' plug, the 2-pin BL7, goes straight to the leisure battery (through a fuse labelled 'Zusatz-Ladegerat'). If you're not using an additional mains charger this plug is a good way to connect to the leisure batteries.

 

[dathers]

So if I look at the BM it has 3 leads Red Brown and Black, black earth, red leisure, brown vehicle, I can see that from the pic that the brown vehicle is spliced into the red on the ebl, I get that the red to the ebl given german/european colouring will be the vehicle so I assume thats where it picks up the voltage, and assume that any voltage drop would only be picked up by default when the vehicle isn't running or its not connected to EHU.

So if I were to connect the BM brown to the main vehicle red lead, then but the bm earth and remaining leisure (bm red) into the additional charge BL7 slot i still don't get how it then magics power from the leisures and pushes it to the vehicle.

Apologies if the above is just stupid - but I am simply trying to get my head round it.

^{_{Subscribers  do not see these advertisements}}

 

[dathers]

oh and if I were to use that configuration would the power usage from the leisures get picked up via the battery monitor?

 

[autorouter]

I'm no expert on the Batterymaster, but I assume there's some electronic control circuitry inside it, with bits to measure the voltage of both batteries, logic circuits to switch things on and off, and one-way valves to stop current flowing the wrong way. It's not just some dumb relay switch, it knows what it's doing.

 

[autorouter]

oh and if I were to use that configuration would the power usage from the leisures get picked up via the battery monitor?

The shunt resistance for measuring the leisure battery in/out amps is on the positive side just where the thick cables enter at the back of the EBL. If you splice into these thick wires outside the EBL, the Batterymaster amps drain from the leisure batteries will not be counted, and so will not register on the display. If you connect through any of the plugs and wires on the front, everything will go through the shunt, so will be registered correctly.

^{_{Subscribers  do not see these advertisements}}

 

[dathers]

OK great appreciate the info, so if I've got this if:
I wire as per my earlier post, and splice into vehicle red lead (as per the ebl 119 pic) and attach BM brown, then connect remaining BM leads to (ebl 101) BL7 the magic in the black box will sort the charging to vehicle battery out and everything will be picked up by the battery monitor?

 

[autorouter]

Yes, that looks OK. Just bear in mind I haven't ever fitted or used a Batterymaster so I'm only 99% sure until I try it out for myself.

 

[dathers]

Great thanks, I clearly am new to all this, the biggest problem I have getting my head around is I accept the voltage from the starter can be determined via the spliced cable, but its how it then knows and controls how it gets charge from the leisures and distributes to the vehicle via BL7.

I guess its leap fo faith time though, thanks again for you help.

^{_{Subscribers  do not see these advertisements}}

 

[funflair]

So if I look at the BM it has 3 leads Red Brown and Black, black earth, red leisure, brown vehicle, I can see that from the pic that the brown vehicle is spliced into the red on the ebl, I get that the red to the ebl given german/european colouring will be the vehicle so I assume thats where it picks up the voltage, and assume that any voltage drop would only be picked up by default when the vehicle isn't running or its not connected to EHU.

So if I were to connect the BM brown to the main vehicle red lead, then but the bm earth and remaining leisure (bm red) into the additional charge BL7 slot i still don't get how it then magics power from the leisures and pushes it to the vehicle.

Apologies if the above is just stupid - but I am simply trying to get my head round it.

You are connecting the leisure batteries to the starter battery as that is the way that the power will flow, so the Red BM has to connect to the leisure battery (in the photograph this is via the solar input plug as this goes to the leisure batteries) the -ve also goes this way and is common to both batteries, the Brown then has to pick up a permanent live to the starter battery so again in the photo "block 2" pin 1 Red is the starter battery connection.

The BM then sees a difference of something like 0.65v and then it will trickle a few amps from the leisure to the starter battery.

On our van I just happened to have +ve and -ve posts in a box all together so that was easy for me but we are not Electroblock.

Martin

 

[dathers]

Thanks Martin, get that, I guess its how the link from a EBL 101 BL7 (which is reserved for an additional charger) facilitates connection to the leisures to draw power - the way my simple brain works is if BL7 is designed for and additional charger won't it be expecting input power for the leisures - and not be expecting to draw power from the leisures to transfer to the vehicle battery.
Guess I'm over thinking it, I know how to programme computers but I couldn't rewire the electrics.

Thanks again Dave

 

[autorouter]

if BL7 is designed for and additional charger won't it be expecting input power for the leisures - and not be expecting to draw power from the leisures to transfer to the vehicle battery.

According to the EBL101 wiring diagram, the BL7 internal connections are simply ordinary wires, no 'one-way valves' or anything like that. So current should flow unhindered in either direction. It relies on the internals of the charger (or Batterymaster) to make the current flow the way you want.

Don't forget to fit the 'Zusatz-Ladegerat' fuse, or you won't get any current at all flowing. A 20 amp fuse, as on the front panel label, will protect the wiring, but you could fit a smaller fuse, maybe even 5 amps, if you can't find a 20 amp one. It's not any safer, just may be more convenient.

^{_{Subscribers  do not see these advertisements}}

 

[dathers]

it must be magic, all that stuff connected and it knows how to take power from one set of batteries and send it to another. In my past IT world you need a whole host of MAC or IP addresses with synchronisation and handshakes everywhere - anyway its time to get off the fence and fit the thing!

As soon as I get the EBL 2 pin cable connector I ordered earlier I'll wire up, and I'll post some pics when its done.

Thanks Dave