Electric water pump control
 

I have asked this same thing in adaptronic -forum, but it is still little bit unclear to me :blush:

How do I control electric water pump with adaptronic 440? Okay I have to use PWM-controlled port and maybe some diode if my pump is rated over 3A, but what port am I going to use?

I have a single turbo, direct fire and no OMP nor AC. Waterpump is Pierburg CWA-400 (400W, 10000 rpm, 150 lpm @ 0.80 bar). Ecu: Select RX-7 S6 pnp.


Thank you very very much!
JP

I am not familiar with teh pin out on the PnP but, you will need to drive a high current solid state relay with the PWM output from the ecu, there is no way the ecu output will be capable of the full earth current of that pump motor.

How is the pump intended to be controlled? What does the manufacturer call for?

I called Meziere and they said PWM is the ideal way to control their pumps if you are aiming for multispeed setups.

The pump is going to be controlled with Adaptronic. The pump is from BMW and the ECU controls it there I guess.

The PWM-control is the best way I suppose. But how exactly do I do that with Adaptronic? Via relay, but from where I take the control signal and what I have to do with WARI?


JP

Doesn't the BMW pump have the solid state relay built into it? Pretty sure you just have to supply the proper PWM signal.

With Haltech and Syvecs, we've built 3D maps with coolant temp v. RPM as the axis to control the output. Realistically, a 2D map with coolant temp as the axis should work fine.

Good point! It might have relay build in. I have to check that out as soon as I get the pump (still in transit from US).

Who knows where I'll get the proper PWM-signal from Adaptronic? Which port?

Thanks!
JP

I looked through Wari this morning and didn't see a way to properly configure an output to run the pump. Need to get Elliot to weigh in on what's possible.

Thats would not be good.. One big reason why I did buy adaptronic was possibility to control different systems with one computer (water injection, water pump..). I really hope there will be some good way to do that. Thanks Ludwig! I hope your contacts will find a way :)

JP

Hi guys,

I found this when I was doing a bit of search - BMW Pierburg Electric Waterpump Controller - Miata Turbo Forum - Turbo Kitten is watching you test compression.

So basing from that, the pump pinouts are:
Pin 1 is battery voltage
Pin 2 is PWM signal
Pin 3 is a test/BSD signal
Pin 4 is Ground

One of the ECU Aux outputs 1, 2, or 3 should be connected to Pin 2 (with a pull-up resistor) for PWM control (only Aux 1 2 3 are PWM-capable). You might run out of aux outputs though if you're using 4 ignition channels, boost control and idle control (going direct fire disables aux output 1).

You might want to do it coolant-based instead of RPM. If the engine is already hot you will want it to keep running at full speed or at least fast enough not to cavitate. Here's an example how to set it up in WARI (attached).

Thanks.

Here's the pinout document for the S6 plug-in by the way.

Another way of doing this (2-stage / non-PWM controlled) is to have a big resistor in series with the water pump so that just keeps a small amount of water circulating, and then when the engine gets above say about 60°C, an aux output turns on and drives a relay that shorts out the resistor so the pump runs at full speed (A bit of a waste having that nice controller in the pump motor though).

Thanks.

Thanks Mark!

Very good and clear information. That was exactly what I needed :)

Situation is not so good though. I do run out of PWM AUX -ports. I'm going to use direct fire, boost control and idle control. I would also like to have water injection control and water pump control. Damn.. I have to thing about if I'll dump the idle control. Boost control is more important..

If I only would have bought e1280s... :(

JP

The resistor lowers voltage. Most dc motors do not like to run at lower voltage.

However. You can get a pwm controller that converts a steady voltage signal into a pwm output.

You would really want to speak to the manufacturer of the motor before running it low voltage to control speed. I have yet to find one that recommends or warranties the motor in that case.

http://www.canakit.com/30a-motor-spe...oller-pwm.html

Ypu could use something like this.

Remove the rheostat and use the input voltage pin to give it your resistance signal. Run that as your normally closed pin off a relay. Then have the signal switch over to a zero resistance signal (or the max input of the controller for 100% duty cycle) on the normally open pin of the relay.

This means your ecus can control the water pump, at least between two speeds, with a simple on/off pull to ground output. Thus saving you a PWM output.

You need another PWM out to run the tach as well.