It is many years since I have performed these calcs. I want to use a 0 – 100 amp scale meter as a 0 -100% PV insolation meter. The reason is that I cannot normally measure insolation as a simple factor of total current out from my PV array as the charge controller is constantly changing that value to suit battery charging needs. However I have another very small array of 11.25 amps max which is directly connected to the battery bank so as not to increase the already maxed out amps of my controller. The beauty of this is that it appears to be always a direct ratio of amps out to % insolation (irrespective of main controller output) with a max ever noted of 11.25A (presumably 100% insolation) So I need a shunt for this meter that will give 100% FSD at 11.25 amps, the meter is a 75 mV coil.
So my very rusty math tells me; I need a shunt which is 0.075/11.25 or 0.00666 ohms.
Am I right or did I screw up?
So my very rusty math tells me; I need a shunt which is 0.075/11.25 or 0.00666 ohms.
Am I right or did I screw up?