IC Spray

[Andy Drummond]

Hi Just configured a G4 using latest firmware to run electric water pump. Part of the logic at low temperatures (ECT) is the need to duty cycle the pump on (PWM). The IC Spray operation works as duty cycle based on time. Have aux output (Aux 4) as GP PWM which gives voltage (PWM) to the pump. Its logic is If ECT > 55 or IC Spray = 1 then operate PWM from graph. Switch off delay is 0.1 seconds So have setup IC Spray as an virtual aux output(2) and another virtual aux output(1) as switching on function. Would only operate once or not. Engine rpm > 450rpm Found work around To get it to run as continuous duty cycling, made the condition of switching function aux output(1) NOT equal to the IC spray virtual aux output(2) ON. That is looped the 2 virtual aux outputs together. With the switch off delay set on the working aux output the duty switching worked. Is the IC spray been designed to operate continuously or as one shot?? Enclosed the link file so you can see the setup. Not the easiest to put in to words. Cheers Andy

Ermolli20100718.pcl

[Jurgen Biggelaar]

Hi Andy.

Probably the best way to describe this would be as follows:

You have 10secs Spray Period & 15% DC.  In short this means 15% of the 10secs water will be flowing, and for the remaining 85% of the 10secs, it will rest (no spray).  Then it starts the cycle again...  15% of the time on, 85% of the time it will rest and so on.

If set to resume it will carry on the cycle from where it left off when the conditions are met again, and in contrast the reset option will start it from the beginning of the cycle when conditions are met again. 

Why you would want to do this with a PWM table makes no real sense (if you are actually using the function for IC Sprayer that is).  The reason being, DC of the IC Spray function will for example turn of for 50% of the time, and then on for 50% of the time if DC is set to 50%.  You need this with this function as the idea is to spray it, then stop and allow the evaporation take care of the cooling, then it's hit again and so on.

Using the PWM table is probably not ideal, unless I don't completely understand what you are trying to do, as 50% DC in this table means on/off/on/off/on/off/on/off/on/off/on/off very quickly to achieve an overall 50% (like a boost solenoid).  This in effect would drive the water sprayer 100% of the time, but at 1/2 speed.  This does not allow time for the Spray to evaporate, in turn giving you an inefficiant method of intercooler 'cooling'.

I hope that answers your question.

 

Jurgen

[Andy Drummond]

Hi Jurgen Thanks for the reply. What I am looking for is to control a electric water pump that replaces the fan belt driven engine cooling water pump (ECT). What would be nice is to have standard Link function which controls a electric engine water cooling pump. Since that Link function hasn't happen yet, I have to develop the control logic to do it myself. In doing this the IC spray function gives some on the logic required. Except I think the IC spray function is not operating correctly. Cheers Andy

[Phil Williams]

Hi Andy,

Basically you need a function that doesn't yet exist in the ECU - GP Timers. There have been several requests for these and it is something that we are going to do.

I think you will be looking around the end of October before this becomes available.

For now, possibly just run the water pump like a conventional pump using PWM while the engine is running.

Thanks,

Phil