safety relay komatsu pc25-1, 40-7

[phankhoa83]

Dear all
I am learning the electrical system of Komatsu pc 25-1, 40-7. i have recognized that safety relay has 6 way as: B, C, E, P, ACC, S. Could you help me For explaining the function of ACC pin. Thank you for your help

 

[007]

Can you scan your circuit diagram or documentation you are reading and post it please.

 

[phankhoa83]

Here is the electrical schematic of Komatsu excavator Pc25-1. I have marked the yellow areas in drawing. Thank you for your help.

 

[007]

Normally they show the internals of that relay so i have to guess unless you have internal circuit.
If the relay was easy to get apart without breaking you could take picture and i could work it out.

Firstly on my machine I cannot start the machine unless the controls safety lever is up.
Can you confirm that yours will start in the up or down position but controls only operate with the lever down?

If that is a yes to that question then they are just performing simple logic before start signal is enabled.
Start signal will be passed through to the starter if.
Start signal voltage is present on C.
The Controls Safety solenoid is at least powered up confirmed by ACC voltage present.
No voltage present on P indicating alternator not operating.

Regards