SSR
Operating Instructions
5/10
Vers. 2.3 © ehb errors excepted
Component Description / Function
The
SSR
protects the starter, the pinion and the engine sprocket. It prevents accidental starting when
the engine is already running or when it is still shutting down.
The
SSR
is an electronic relay that is switched between terminal 30 and the starter (terminal 50f). The
engine speed is measured at terminal W of the alternator. The connections on terminals 15 and 31 are
for supplying power.
The D+ connection is required for some alternators for extra excitation. During the start operation, the
SSR
switches on voltage to the D+ connection in parallel with the charging light. This ensures that
even at low speeds, the W terminal provides clear signals for speed detection.
2.1 The following conditions prevent the start-up process:
-
There is already voltage present at input terminal W.
-
After each start attempt, the ignition must be switched off for at least two seconds.
-
After 6 seconds, a new start is possible.
2.2 The following conditions interrupt the start-up process:
-
The frequency at terminal W exceeds a specified value.
2.3 Scope of Protection
-
Start inhibited while the engine is running
-
Start inhibited while the engine is shutting down
-
Restart inhibitor
-
Turning off the starter when exceeding the frequency (200 Hz) at terminal W.
-
Start length is limited in time
2.4 Safety Concept
-
The SSR is plus switching.
-
All outputs are protected against overloading by short circuit detection.
-
In case of overload, the current at the outputs is limited.
-
The output transistors switch off in case of overtemperature.
-
While the restart inhibitor is activated, the SSR does not require any power supply.
-
For switching, the output transistors require a release from the processor and voltage
at input 50e (redundancy).
