Driving A Large Pwm Pump - Dhb Or Solid State Relay?

[Gav]

As part of my upgrade I'm installing a single large fuel pump rather than 2 pumps in parallel.

Most aftermarket ECUs can output a PWM signal based on selected parameters (eg injector duty, rpm, manifold pressure etc).

My question is what is used to switch off and on the pump? I see Motec has a purpose built dual half bridge amplifier for such a duty.

http://www.motec.com.au/dhb/dhboverview/

This is only rated at 20A continuous which may be inadequate for this pump at full speed.

Can a solid state relay be used or will this not be up to the task of switching at many times per second that the PWM signal will request?

Cheers

Gav

[kitto]

http://aeromotiveinc.com/products-page/accessories-electronics/16306-billet-fuel-pump-speed-controller/

Pricey but rated to 40A.

What pump are you using and whats the maximum current draw.

Fuelab pumps have built in PWM contollers. They just require a 500 - 1500Hz input.

[Gav]

^{Thanks Kitto - these are quite crude and only have a high/low switch point. I think they also require an old style tach signal from the coil.}

^{I'm using an Aeromotive Eliminator pump - not sure of the maximum draw.}

^{Surely someone here must have set up a PWM output to control a fuel pump .}

[SimonR32]

I don't know if you have purchased the pump yet Gav but have you considered a Magnafuel?

They don't need any PWM control and mine has not even got luke warm, let alone hot.

[Gav]

Thanks Simon

I have one of the Eliminator Stealth kits on the way which will let me easily construct a "pump in surge tank" setup similar to the Sard tank I had previously.

After speaking with more people it seems that a simple high quality SSR will do the trick.