Visit our Popular Forums

sv.antea · 20-03-2017, 11:12

Please help. Bought Victron BMV-702 a year ago, finally getting around to installing it, but now I can't find the UTP cable that came with it. Question: do both both connectors on the factory cable have the same pin-out, that is same colors left to right or are they reversed as in some types of interconnection (patch?) cables? (not familiar with the terminology) I can make my own cable of the right length, but not sure which way to crimp the connectors. Thanks, Stan

Stu Jackson · 20-03-2017, 11:25

Have you considered asking Victron?

sv.antea · 20-03-2017, 11:37

Yup, sent e-mail, but I confess, as I was about to drive to town, where I could pick up the cable, I used the shotgun approach and bugged everybody at once, on chance someone will respond in time. Sorry. Anyone out there with access to both ends of the cable? Much obliged, Stan

fallingeggs · 20-03-2017, 13:17

I can take a look this evening!

john61ct · 20-03-2017, 18:15

Victron cable is UTP - Cat 5E or 6 for long runs,

RJ-12 connectors (all 6 pins)

straight through like phones, not swapped like ethernet

pin-outs

1 - blue
2 - orange
3 - green
4 - white green
5 - white orange
6 - white blue

not using the white brown/brown pair

Dod42 · 20-03-2017, 18:39

Try and keep the cable run as short as possible, as mine always reads about .1 volt under actual which I blame on voltage drop across the UTP cable

fallingeggs · 20-03-2017, 19:37

The above beat me and is what I see, so there ya go.

smac999 · 21-03-2017, 22:40

Quote:

Originally Posted by Dod42

Try and keep the cable run as short as possible, as mine always reads about .1 volt under actual which I blame on voltage drop across the UTP cable

Does it send analog voltage up the cable? Or process at shunt and send data? The shunt seems to have a bunch of electrics on it. I always figured the later.

Dod42 · 21-03-2017, 22:51

Quote:

Originally Posted by smac999

Does it send analog voltage up the cable? Or process at shunt and send data? The shunt seems to have a bunch of electrics on it. I always figured the later.

Short answer is I don't know however I have put a meter on the utp cable at the meter end and the voltage is about .1 below what is at the battery/shunt end, so I'm assuming the measurement is done at the meter end based on what it is being supplied by the utp cable.

Dod42 · 26-06-2017, 16:50

I have been chasing a problem with my bmv702 showing 0.1 volts below actual. I felt I had a faulty Bmv. But before I sent it back I borrowed another and configure it the same. I also changed the cable and shunt. It shows the same drop. Turns out that if, like us, you use the relay on the bmv then if you set it to mode inverse (meaning always closed unless trigger event reached) then the bmv shows about 0.1 below actual. Sounds small but with LifePo4 batteries that's a big difference. If I stop using the relay in inverse mode it shows correct voltage on both units so it's an issue with relay draw causing the voltage drop

sv.antea · 26-06-2017, 17:24

I have recently installed BMV-702, haven't experimented yet with all the functions, but I already noticed the voltage reading drops .02 to .03V when the back lighting comes on. And that is after I shortened the included cable to 6ft. Apparently it reads the voltage at the display and there is slight voltage drop in the cable. I was hoping the voltage was converted to digital signal at the shunt, but already noted there wasn't enough stuff on the little ckt board.

sv.antea · 26-06-2017, 17:33

Thanks DoD42, good to know about the relay draw. I am planning to go to LiFePO bank and indeed, 0.1V is too much play. And by the way, as soon as I got a Victron sales rep to promise to send me a new cable, I found mine. Fortunately, the cable from Victron rep never arrived.