Hey Mr M - point me to that post of yours where you measure all the points on the Dibi, cos i don't want to re-read the entire thread looking for it, but i want to do a before and after when i mess with this new spring Dibby is giving out.
Thanks!
T
I would have to look it up also, but I just did another round of measurements playing with the little BeCu strip Peter gave me to replace the fuse with if I wanted to. I made several measurements and thought I had hit pay dirt, but reassembled stock after cleaning and the improvement I had found was still there. Seems that removing the button and cleaning all the contact surfaces did as much as the BeCu strip did in place of the relay contact I showed earlier. Here is the events as they went.
Measured battery + to brass post on the other side of the fuse. 44mV (.044V)
Measured from non battery side post of fuse to + post of an RM2. 49mV
Measured from battery - to - post of RM2 139mV
Measured from aluminum plate at far end of plate button side to - post of RM2. 20mV
Installed BeCu strip like I did the relay contact and from battery - to - post of RM2 3mV (yes a 135mV improvement!)
I cleaned the aluminum button post and screw and spring and spring seating area and reassembled with BeCu strip installed for a test to see if any more improvement could be had. 3mV
I removed the BeCu strip fully expecting to see 139mV again. 3mV!!!!!!!
Tested whole system again
SX30 battery unloaded 4.08V
SX30 battery loaded (.7 ohm coil in RM2) 3.93V
Posts of RM2 3.84V
The battery had .15V drop from internal resistance.
That is only a .09V (+-.01V on that scale) mod voltage drop with a .7 ohm coil.
Seems that all it needed was a cleaning of the aluminum, not a redesign.
The majority of the voltage drop is in the battery internal resistance, fuse, brass center post, etc to + post of RM2.
Going to replace the brass center post with copper, but don't have time today.
I am going to put some Noalox on the aluminum parts and watch it over the week.