Closed loop fuel pump setup

j.oe
Posts: 21
Joined: Sun Jul 15, 2012 11:19 am

Re: Closed loop fuel pump setup

Post by j.oe » Sat Sep 07, 2013 11:20 am

I currently use two denso 1020 intank fuel pumps that work in parallel mode in my Supra MKIV. The negative power of both i connected to the flange plate without any insulation. Outside of the flange theres a M6 bolt the GND is attached to. So i can use each of both contacts of the original power connector feeding insulated through the flange plate for the +12V power of each pump. The idea is to share the current load to both contacts of the plug.

On the other hand a H-Bridge setup cannot be used, as one side of each pump motor is fixed to GND. Further way there's no H-Bridge control needed at all. The pumps never will work in reverse or brake mode.

My idea now is to apply a half bridge driver to each pump. For example this board http://www.ebay.de/itm/BTS7960B-43A-Mot ... 3224376%26 coud be used.
An external 5V auxiliary supply will be needed as well as a 5V pullup plus a TTL inverter, if there not all PWM and control stragegies shall be inverted in the syvecs setup.

What do you think about that ?

stevieturbo
Posts: 834
Joined: Sun Dec 07, 2008 2:04 pm

Re: Closed loop fuel pump setup

Post by stevieturbo » Sat Sep 07, 2013 10:54 pm

Racetronix sell some insulated connectors for passing through the tank

This kind of thing, but they do a few different ones.

http://www.racetronix.biz/itemdesc.asp? ... 01&eq=&Tp=

MikeyB571
Posts: 40
Joined: Sat Nov 26, 2011 12:05 pm

Re: Closed loop fuel pump setup

Post by MikeyB571 » Thu Nov 28, 2013 5:16 pm

Pavlo,
Thanks for you help on this, I have mine all setup now. I kept the fpr and just have an open loop setup driving both lift pump and one of my 044's. The other 004 is just on a relay and comes in at a set injector duty.

It all works great and I can't believe how quiet the pumps are now, basically I never hear them.

I am still concerned about reliability but we will see.

pavlo
Zen Performance
Posts: 406
Joined: Mon Aug 04, 2008 9:18 am

Re: Closed loop fuel pump setup

Post by pavlo » Thu Nov 28, 2013 7:06 pm

Awesome news, thanks for the feedback. What PWM board did you go with in the end? The one I linked to on ebay?

Cheers

Paul

XKLABA 1
Posts: 34
Joined: Tue Sep 03, 2013 8:08 am

Re: Closed loop fuel pump setup

Post by XKLABA 1 » Sat Dec 14, 2013 2:31 am

just a quick question and I'm sure this is gonna sound dumb but the fuel control pwm out put is a positive feed ?

I'm getting the circuit built for the negative side of the pump and the guy making it asked me to make sure of the feed is + or -

Benkku
Posts: 50
Joined: Mon May 02, 2011 11:30 pm

Re: Closed loop fuel pump setup

Post by Benkku » Sat Dec 14, 2013 10:43 am

stevieturbo wrote:Racetronix sell some insulated connectors for passing through the tank...
I think that 'forget those', because no proper information is given - instead they hide it.

Much better solution is to use proper FTC connector, for example from Deutsch Autosport series.

http://www.deutsch.net/en/browse-produc ... -tank.html
http://www.deutsch.net/content/dam/te/d ... manual.pdf

Benkku
Posts: 50
Joined: Mon May 02, 2011 11:30 pm

Re: Closed loop fuel pump setup

Post by Benkku » Sat Dec 14, 2013 10:53 am

XKLABA 1 wrote:just a quick question and I'm sure this is gonna sound dumb but the fuel control pwm out put is a positive feed ?

I'm getting the circuit built for the negative side of the pump and the guy making it asked me to make sure of the feed is + or -
Usually feed is positive and 'constant' - so pulsing is made on a negative side, altought it depends from the switching component used.

XKLABA 1
Posts: 34
Joined: Tue Sep 03, 2013 8:08 am

Re: Closed loop fuel pump setup

Post by XKLABA 1 » Sun Dec 29, 2013 10:16 am

ok so I am setting up the pump speed control, at the moment I have Fuel pump 1 out put switching two relays, one for lift pump and one for main pump, can I just reassign Fuel Pump 1 to FP 2 and have it turn on the relays then run a new wire to the switching unit with the PWM signal and connect it to one of the IGN out puts ?

If so which one should I use ?

the switching unit will take both positive or negative, I was going to use a TTL out put unless there is a better way ?

Cheers, Michael

pavlo
Zen Performance
Posts: 406
Joined: Mon Aug 04, 2008 9:18 am

Re: Closed loop fuel pump setup

Post by pavlo » Mon Dec 30, 2013 1:21 pm

Use ign 7 or 8 with TTL (7 if using TTL for coils, 8 if using normal for coils)

You are using a full H Bridge controller, it will be perfect for the job, just check your duty cycles as and direction. You will likely need a minimum of 35% to get the motor running sensiblly.

The lift pump/main pump setup isn't ideal I'm afraid as the strategy doesn't current cater for this specific setup, I have done as you have suggested and used fuel pump 2 for the lift pump with 0% minimum duty, and fuel pump 1 for the PWM control. You can leave the power for the PWM control to just be ignition switched, it doesn't need to be powered on/off with the fuel system, the PWM control is enough.

The only caveat with the above is that the lift pump will not run until the run mode is "CRANK" or "RUN" so priming the system from bone dry will require the lift pump to be manually activated.

I will be putting in a request for a specific lift pump output option.

Cheers

paul

MikeyB571
Posts: 40
Joined: Sat Nov 26, 2011 12:05 pm

Re: Closed loop fuel pump setup

Post by MikeyB571 » Tue Dec 31, 2013 8:54 am

Pavlo,

I had the same problem with the lift pump not priming and I decided it would be nice to have the lift pump setup with pwm control as well as the main pumps.
So I have a dual channel h-bridge, one channel driving the lift pump and the other the main pump. Then I use a single pwm output from the syvecs to drive both channels. This means that the lift pump will always be using the same duty as the main pump but I don't think that will be a problem as the lift should always be ahead. It seems to be working fine but I haven't mapped it properly yet.

Michael.

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