fit on a 1000/100 shunt?

[jtdiesel65]

I have a 1000/100 shunt and not a 500/50. I would imagine that the WBjr will not bolt up to a 1000/100 shunt due to bolt pattern. But, can you place the WBjr away from the shunt and run leads from it to the shunt so it's not directly mounted on the shunt?

thx

[Jay c Swartley]

Hi jtdiesel65,

I am a newby too. I had the same problem.  Ryan will hopefully confirm this for you but what I was told is (I have done this successfully) bolt the side of the WBjr opposite the purple wire directly to the inverter side of the shunt using the supplied bolt (machine screw). The other connection closest to the purple wire you may use a wire (supplied by you) I used a 18 gauge stranded with a solderless (crimp) connector and bolted to the terminal access hole with a machine screw, lock washer and nut.  Run the other end of this wire to the battery side of the shunt and attach probably with the other supplied machine screw.  Of course run the purple wire to your Classic.

This was easy and should work. It has been a couple weeks since I did this and still have not been able to verify the WBjr is working. There is an ongoing issue with the Classic firmware update and I like many others, are having trouble getting the Classic to update.  My understanding is if you do not have version 1758 or newer, the WBjr will not work. So check your version.

Good Luck

Jay

[brad.midnite]

As the Whizbang Jr. uses the shunt both as a current return and a point of measurement it is important to get a good, solid, electrical connection between the Whizbang Jr. and the shunt. Additional resistance in series between the WBJr's current return path (right-side terminal with wire sticking out to the left) will manifest as a current offset caused by the meager power requirements of the WBJr.

So here's what I would reccomend. Bolt the right-hand terminal of the Whizbang Jr. to the system-negative side of the shunt, i.e., the common negative connection for all of your equipment, e.g. The Classic and whatever else you have. Take a wire and secure it between the shunt and Whizbang Jr's left-hand terminal. The resistance between the left-hand terminal and the shunt is less important, so this technique will yield better results than running wires to both terminals or bolting the left-hand terminal to the shunt and running a wire to the right-hand terminal.

-Hope that makes sense
-Brad

[jtdiesel65]

Thanks for the info. I'm not sure I'll be able to bolt it to shunt due to wire congestion. I've already gone ahead and used ~20" leads to attach it to the shunt. I do see about a 1 amp difference between the WBjr and the trimetric.  I'm not sure if that's normal as I would expect some difference or due to the extra wire lengths.  From my perspective, the 1 amp doesn't matter as long as I can get an SOC reading that is close to actual.

I was able to update my firmware to the latest. However, a couple years ago I had to get a new circuit board from midnite for one of the classic because it wouldn't take the firmware.