Whiz Bang Jr. Install Qestions

[justinbowser]

Totally newb question but after reading the instruction sheet that came with my WB jr I see no mention of where the shunt is to be installed.  I am assuming the shunt should go in the negative line coming from the Classic 200SL to the battery bank, correct?  Also, I have a Bayite meter monitoring the CC output and would like to keep it but it uses a different shunt value (75 mv) than the WB, can I just hook them in series or will the miniscule voltage drop introduced by the Bayite shunt interfere with the wB?

Thanks,

Justin B.

[ClassicCrazy]

Yes the whiz bang shunt goes in the negative line - it should have the only one connection on one side and that is from the battery - all other negative connections will be on the other side.  The instructions tell which way the wire coming off the whizbang should be oriented.
I don't know about you other question - seems to me like it wouldn't make any difference if there were two shunts in series - as long as you put one side towards battery and all negatives on other side. So if they were in series it would be negative from battery to whizbang shunt other side of whizbang shunt to the other shunt other side of that shunt to all other negatives in system.
Maybe someone else will say why this wouldn't be good.
Yeah too bad the shunts were the same value then you could have just used one for both .

Larry

[justinbowser]

Larry,

Thanks for the help.  Yeah, would have been nice to be able to use one shunt but that would be too easy! 

Regards,

Justin B.

[Vic]

Hi Justin,

Agree with CC Larry.

One question:  What is the existing 75 mV Shunt's rated current value  (what current equals 75 mV)?

Thanks,   Vic

[justinbowser]

Vic,

The Bayite meter shunt is rated at 100 Amps.

Justin B.

[ClassicCrazy]

I was wondering what meter a bayite is so I looked it up . I have some of those I use here and there - different names I got them from Aliexpress .
Not sure I would want to put the cheap shunt that came with mine in my main line. When you get your Classic hooked up and running you can use Grahams android Classic Monitoring app - gives a lot more data and is portable or easy to mount a cheap phone of tablet on the wall.
Here is photo of two of the meters I have - one on left is AC version that uses a CT which is 30 feet away on output of my inverter.  The DC one I just use to monitor output of my 24 to 12 dc to dc converter.
Being able to get $10 meters like this makes me reflect to starting out in solar 30+ years ago reading Home Power magazine on how to make an expanded scale voltmeter.

Larry

[Vic]

Vic,

The Bayite meter shunt is rated at 100 Amps.

Justin B.

OK,  Thanks Justin,  for the info.

There is a Scale Factor in the Classic,   but,   it has a limited range.

Based on what CC Larry mentioned,   would not want to place the existing Shunt in series with a  name-brand 50 mV 500 Amp shunt.

FIWI,   Vic

[justinbowser]

OK, I get the picture.  I suppose I can move the cheapo meter to the output of the 24-12 converter as in CC Larry 's configuration.  I run my HAM radio and the pump off 12V.

[ClassicCrazy]

OK, I get the picture.  I suppose I can move the cheapo meter to the output of the 24-12 converter as in CC Larry 's configuration.  I run my HAM radio and the pump off 12V.

Yes I am also a ham as is Vic and quite a few others on here.  I think you will save yourself some hassles down the road.  I don't know why all those inexpensive meters use 75mv shunts  but they do .  Maybe some reason because of the chip they use in them.

Larry