Author Topic: Wizz Bang Jr, install on modified shunt  (Read 102 times)

mike cunningham

  • Newby
  • *
  • Posts: 11
Wizz Bang Jr, install on modified shunt
« on: February 14, 2021, 09:24:30 AM »
Hi all. I am using the marinized Kid aboard a boat in a relatively low power application(200 watts solar).

I wanted to relate my install experience for the record, may help someone else with the same issue.

My boat is equipped with a 2007 vintage Xantrex battery monitor and associaled 50 MV 500 amp shunt. I bought a the Kid controller four years ago and ran without the WB on three 210 AH Lifeline AGMs since that time. However the AGMs had also been in my boat since 2007 so they were getting pretty long in the tooth. I decided to replace the Lifelines in mid 2020. Got 13 years out of the batteries so I am pretty happy with batt longevity. However I was only using the solar system during long distance ocean races.

I replaced the Lifelines with VMAX Tanks 115 AH AGMs and have been doing more cruising where I need solar full time. I wanted to ensure the Kid was not overcharging the batts due to the inability of the standard Kid to monitor SOC. To address this I purchased a WB and recently got it operational. I still have a few questions re function but will ask those elsewhere on the forum.

What I specifically wanted to relate is how I addressed the mechanically incompatable shunt. When I received the WB I prepared for the install expecting I would be able to simply bolt the WB to the shunt, reconnect the "cooperative" batt monitor leads and done. However I found the screw pattern on the shunt was not the same as the WB's.  After doing a bit of Q&A online I decided to save the $60 on a new shunt and simply drill/tap the posts on my existing shunt so the threaded holes were consistent with the WB pattern. I was very careful to stay away from the calibrated resistors (they look like metal vanes) which connect the two shunt terminal posts.

When complete I was able to connect the WB and Xantrex to the shunt, reactivate the system and all good, both the Xantrex monitor and the Kid are now operating and I am getting battery monitoring performance from both. I still need to evaluate how closely the Xantrex and the Kid mirror one another and a little "settings tweaking" may be necessary but all seems to be functioning as it should.


  • Hero Member
  • *****
  • Posts: 2843
Re: Wizz Bang Jr, install on modified shunt
« Reply #1 on: February 14, 2021, 11:40:56 AM »
Nice hack !
Nice to save the $ and use what you have.
Good that you got good lifespan from your batteries - the SOC is a valuable tool to know what is going on with them.
In case you are in US - I  get my shunts for Whizbang from Northern Arizona Wind Sun ( maybe Deltech brand ?) and they are less than $30 .
I see the Midnite branded one is lower in cost now too close to Deltech .
Happy Sailing

system one
Classic 150 , 5s4p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system two
Classic 150 ,5s 135 watt Kyocero , 16s Calb 100AH LiFePO4 , Outback VFX 3648 inverter
system three
Midnite KID MPPT 24 DC in to  12 volt AGM batterie