Hello Everyone,

MPC-20 Standard Config - Advanced Version
PowerVision 2.7.10514 MPC-20 MSTD Patch 4
Windows 8.1 x64

Short summary: The clutch will not disengage when the engine state is Cooldown and current engine RPM is below the clutch disengage setpoint.


Regarding the AT Load (Clutch) feature of the MPC-20.

Here are a few setpoints I believe to be relevant for reproducing the reported behavior.

Throttle Type: Pulse INC/DEC (i.e. mag pickup or frequency generator if your testing from a bench)
Min RPM: 850 RPM
Max RPM: 2800 RPM
Clutch Engage RPM: 1250 RPM
Clutch Disengage RPM: 950 RPM
Warmup Delay: 3 minutes
Cooldown Delay: 3 minutes
Warmup RPM: 850 RPM
Cooldown RPM: 850 RPM

I have a relay output set to 'At Load' (Clutch)

Setting the controller to Auto, and performing an auto start via a single switched input,

With regards to engine state logic, transitioning from Warmup to At Load the clutch engages, when transitioning from At Load to Cooldown, and staying in the Cooldown state, the clutch does not disengage, when current engine RPM is below the clutch disengage RPM.

The clutch does disengage when Cooldown ends, and the state changes to "stabilize" or "spindown" and engine is no longer running.

I took a look at the routine in PowerVision, and what might be something to take a look at is shown in the attached images.

It appears that there is a check, prior to checking the clutch logic, to see what "state" the controller is in. I believe that might need to be changed to a OR condition, where one condition is "At Load" and the other is "Cooldown".

Maybe something like the following?

OR(Current_Engage_State = Current_Engine_State_Running_Loaded, Current_Engine_State = Current_Engine_State_Running_Cooldown)

I do not know if such a change will introduce unanticipated complications, or if there are other things to consider, but this is something I have noticed.

Please advise.

Hello Ocelot,

Thank you for the details! It is very helpful. I will certainly log this so that the standard configuration developer will take a look at it.

This should be fixed in the MPC20 config that will be in the PowerVision Configuration Studio 2.8 Patch 1 and the PowerVision for Controllers 2.8 Patch 1 Release.

Stalley,

Thank you for the update, I noticed that this was address with the Clutch and new Gov Control settings in the newer MPC-20 configs.

We appreciate your time and effort spent on these kinds of things.