Monitoring House Battery Current Circuit I

This is a one design circuit instrument to monitor current of battery. This circuit gives a check on operation of the motor home electrics. This is a simple form for design the instrument. This is the figure of the circuit.

This circuit is using Dick Smith Electronics DSE Q2220 3½ Digit LCD Voltmeter Module that is a 200 mV fsd voltmeter. So it will give a direct reading of Amps when connected across the EBL 269 shunt. Four-color ribbon cable to the LT400 Control and Switch Panel is soldered there to points near the main plug connector. There are pads for the current shunt on the circuit board (Pin 1 (yellow) and Pin 4 (orange) near the connector). Since analog voltages for the House Battery (Pin 4) (orange) and Starter Battery (Pin 8) (green) with Common negative at Pin 2 )(blue) are available there too, these are made accessible as touch points on the meter box front for reading with a multi meter. Installed in a wooden box, a photo of the meter is shown with it reading 1.8A consumption (negative current) due to two 10W halogen lights (1.7A) and the LT400 itself (~0.1A). The battery voltage touch points and ammeter power switch are on the left of the meter module. The meter box is attached to the wall by two keyholes in the back, and sliding to the left over countersink-head wood screws.