Wiring Digital Voltmeter Ammeter Without Shunt

I have this:  http://www.ebay.com/itm/271210262267?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649. They say is can it be used up to 10 amps without a shunt, but I can't find wiring diagram. I am trying to wire into 50 watt led light. I know the small red and black go to power source. I am not sure how to connect 3 thick wires( red, black, yellow) without a shunt. I am only trying to meter 1.5 amp circuit.
 Here's what I am trying to wire. Thank you

Picture of Wiring Digital Voltmeter Ammeter Without Shunt

I think you will find the 3 thick wires are for you to wire ammeter directly into the circuit. I did find a diagram but the link wont past in and it is too long so i'll try to explain.

The thick wires seem to be wired as follows. Black straight back to the negative of your power supply. The yellow goes to the negative of your load. The red is to you positive side of load.

The thin red also picks up an active from your power supply but the thin black is left disconnected.

Alternatively you can do as I did and get a shunt. Hope this helps

Ammeter Wiring.jpg