Another item which I have had for a while is a Solid State Relay (SSR). This will be controlled by the MS and will drive the fuel pump motor that is mounted in the fuel tank. This is required as the MS doesn’t have sufficient drive current capability. This SSR is rated at up to 40A and unlike a normal relay, can handle the 125Hz switching frequency.
Update: 6th February 2015
I had a conversation on the MSExtra forum discussing with Jean from www.jbperf.com a designer of addon boards for the MS ECU, the use of this SSR. Bottom line is that at the 125Hz switching frequency from the ECU, this and most economy SSR’s wont be able to turn on due to their turn on/off times being to high. This SSR’s turn on/off times are in the order of 0.5ms… far to slow.
I’ll have to resort to an alternative circuit, one which was mentioned in the above thread. I’ll have to investigate further, but looks like the use of a a low RDS on MOSFet would be the go.