MidNite WhizBang jr Current Monitor Quick Report

VicVic Solar Expert Posts: 3,124 ✭✭✭✭
This is not a real Review, but just a quick report on this new MidNite product.

Have been in use for about two weeks. The WhizBang jr is composed of a current monitoring circuit board which attaches to a Shunt in the low side of the battery (the negative terminal). It communicates with the MidNite Classic Charge Controller. The CC's LCD display (the MidNite Graphic display -- MNGP) displays the status screen of the WBjr on the MN Classic CC, and this data is/can be displayed on the MN software APP. (I do not use this APP at this time so cannot report on this functionality). This Status screen shows the present instantaneous Net battery current, Accumulated Ah, WB temp, and more. See the WB Manual here:


The WBjr communicates with the Classic line of CCs, and with the latest Firmware, has the ability to terminate the Classic's Absorption stage based on actual battery charge current into the battery, not just based on current delivered by the CC (which will include loads or and on the Inverters and any other DC loads on the battery).

The WBjr mounts directly onto a Deltec, or other similar Shunt, and uses a single wire to connect to the Classic's Aux 2 input. The standard Shunt is 50mV 500 Amp. There is a Scale Factor value that can be entered for some other Shunts.

So, in the past few weeks of use, the WhizBang jr has been working very well, and has been ending Absorb, based only on the current going into the battery bank, and not the sum of all loads on the system -- a great improvement over just using CC output current to end Absorb.

There is an additional function in the latest FW for the Classic CC -- Days Between Bulk. This allows the user to specify the number of days that an Absorption charge stage. For lightly-used systems, this CAN help minimize the stress on the battery from a complete recharge on days of very light discharges.

Many of us have been begging MidNite for these functions for a while now, and, like the very customer responsive company that MidNIte is, they quickly developed and began shipping the WBjr and the new FW that supports these functions.

The WBjr is available from Wind-Sun, and sells for an amazingly low US $44.00. The Dletec Shunt is not included, but is installed in a number of MN e-panels and in other manufacturer's DC Conduit boxes (like the older Xantrex DCCB and DCCBLs, etc):


Am very impressed with this very inexpensive battery current sensing/display module for the Classic line of CCs.

Thanks MidNite! Vic
Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH [email protected], 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
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