Ampere meter with shunt from DX.com

[gjrono]

Hi!

Ordered this amperemeter with shunt from DX.com
**broken link removed**

It is described with package content 100A digital ammeter and 100A shunt

But when i received the package from DX.com they have sent me a 100A Digital ammeter, and a 50A shunt.

What will be the concequences of such setup. Will the measurment be faulty, or wil it not work at all, or maybee everything ok, but not measure more than 50A.

My setup for this should be for meassuring charge current on a boat alternator!

 

[pinout]

From the link supplied, I believe the product is basically a 10A meter with a 100A shunt (see the wiring image).
The shunt is just doing its job and bypassing the 90A.

As for what you received? I think it is probably the same meter (i.e. can display up to 100A), but you have a 50A shunt.
My thoughts are this will make your reading approx 2 times the correct current and your safe max current limit will be 50A.

The meter cannot be a basic 100A device in my opinion due to the size of the wiring and power in the sense resistor, hence my "display up to 100A" comment.
This may be OK for the alternator, but possibly not the battery under cold starting conditions. Check the alternator spec.

 

[gjrono]

Yes but the label on the meter is marked for 100A thus i think they mean 100A shunt. Therefor i agree with the supplied shunt on 50A the readings would be wrong.

I assume the shunt must fit the meter settings. Or i might be wrong. Maybe the resistant in the shunts are equal no mather how big the max ampere settings are?

I dont think the meter is 10A either, the wires are very thin!

 

[pinout]

Yes agree, meter is probably made for 100A shunt.

regarding wiring look at (5th pic on original post if this doesn't work)
**broken link removed** or perhaps this link
https://img.dxcdn.com/productimages/sku_226806_5.jpg

I presume you have to wire in the yellow and black power wires that carry the current, so assume these are 10A if the shunt not fitted?
In the figure there is a red lead and black (not used lead) which I assume just powers the display and circuit and the others you have to provide?

I assume the shunt must fit the meter settings. Or i might be wrong. Maybe the resistant in the shunts are equal no mather how big the max ampere settings are?

Yes assume the shunt and meter must match, and yes you could be right on the second point, so reading will possibly be correct, but 50A max ratting?
Could you try with a car headlight bulb?

 

[gjrono]

i just noticed the voltage specified for both the 50A and the 100A shunts on Dx bot specified 75mVoltage. this is probably the voltage drop over the shunt. therefor the readings probably vil be correct no mather what ampere they are rated for.

Il try to hook it up and test.

Thanks for your contribution