Gday all,
Does anyone know the max amp draw off a 044 bosch pump?
rgds
Brian
I\'m buying a fuel pump controller and it has a solid-state transistor circuit, rated up to 40 amps, which replaces the relays recommended in most fuel pump electrical circuits. I\'ll be running twin bosch 044 pumps and I would like to know whether I can connect both bosch pumps to the same controller or whether the current draw will be too high, hence needing to controllers one for each pump. Hence need to know what amps the 044 pumps draw.
rgds
Brian
I believe it\'s around 15.5A max but this will vary with heat and what you are running pressure wise
Quote from: SmbFD3S;681297I believe it\'s around 15.5A max but this will vary with heat and what you are running pressure wise
Thanks for that mate. being completely ignorant of anything electric even my wifes digital camera, when you say it depends on heat I take it the hotter the pumps are running the less efficient so the higher the current draw?
I\'ve heard that bosch pumps should not run less than 43psi I don\'t know whether true or not but i\'m planning to run 44psi base pressure with up to 2bar boost so total of approx 73psi.
rgds
Brian
15.5A is max rated at 75psi which will flow approx 3.3 litres a minute, but yeah the hotter something is the less efficient it is and increases amperage therefore it\'s possible the pump could run at max amps at lower pressures....
I assume your solid state circuit has a heat sink ??
I\'m running one 044 pump with a traditional 40A Bosch style relay and a 25A fuse wired hard in 10 gauge and the relay doesn\'t even get warm just for your info :)
I have no idea it does not mention whether it has a heat sink. What is the heat sinck the hard kind of putty stuff they put a circuit board in?
http://aeromotiveinc.com/products-page/accessories-electronics/16306-billet-fuel-pump-speed-controller/
The two pumps will be running side by side in the fuel tank so they will get warmer due to their close proximity to each other but then on the other hand the fact their in a fuel tank should cause them to run cooler than if they were in the rear boot.
rgds
Brian
Ignore the heat sink comment, i thought you were making up a control board lol, being an Aeromotive bit of kit this will be fine...
Have a look at post number 47 for amperage comparisons:-
http://www.rx7club.com/showthread.php?t=739404&page=2
I would have thought you\'d be ok to be honest. Running two controllers will be a nightmare anyway to setup as there will be variations in the control circuits...
Great find thanks. I\'m suprised the amperage draw was so low for both pumps combined,a nd it\'s the same cjmotorsports kit I have so an ideal comparison.
rgds
Brian
No problem mate :)
If you are running them in parallel though, they\'ll be sharing the pressure duty therefore you\'d expect the amperage to be lower :)
Quote from: SmbFD3S;681334No problem mate :)
If you are running them in parallel though, they\'ll be sharing the pressure duty therefore you\'d expect the amperage to be lower :)
So in effect at idle of 44 psi base pressure set on the regulator, each pump will be running at 22psi hence the lower amp draw?
rgds
Brian
Sorry worded that to be slightly confusing . Not exactly no, both the pumps will run at the pressure you set at the FPR but because you have the pumps in parallel they\'ll flow twice the amount of fuel so never likely to be running at full throttle cos you\'ll never use all the fuel (unless you\'re running lots of huge injectors lol)....
Ok hope im not bugging you by now. So a bosch 044 pump at around 75 psi draws 15.5 amps so if you had two at bosch pumps then the amp draw would be approx 31 amps if you then begin to apply heat and inefficiency then the that 31 amps could be maybe 37-38 amps which not only makes it dangerously close to the 40 amp rated solid state transistor circuit board of my fuel pump speed controller and also the fuel pump speed controller comes with in built 30 amp fuse to two pumps funning at 75psi with not ineffeciency is still 31 amps and would continually blow the fuse everytime I hit 30 psi if running a 45 psi base pressure. So obvious solution would be run less base pressure as two bosch 044 pumps will be flowing a fair amount of fuel at idle, but I have heard but do not know how true it is that bosch 044 pumps should not be run less than 43-44psi is there any substance to this or anyone heard something similar?
rgds
Brian
Not bugging me at all, gets the mind working lol....
To be honest not sure, i know a lot of people run 2 pumps from a 30 amp relay and fuse with no problems but wouldn\'t like to say that it\'ll be fine on a solid state controller... I would assume it would be better to run 2 controllers and set the voltage differently for a given RPM ????
Can i ask what ECU you are using? is this a pure race car? Rotary ? etc.... just for info wise..... and what size fuel lines will you be running i.e. -10\'s ?
Not heard the story about the minimum pressure to be honest so dont know.
Quote from: SmbFD3S;682107Not bugging me at all, gets the mind working lol....
To be honest not sure, i know a lot of people run 2 pumps from a 30 amp relay and fuse with no problems but wouldn\'t like to say that it\'ll be fine on a solid state controller... I would assume it would be better to run 2 controllers and set the voltage differently for a given RPM ????
Can i ask what ECU you are using? is this a pure race car? Rotary ? etc.... just for info wise..... and what size fuel lines will you be running i.e. -10\'s ?
Not heard the story about the minimum pressure to be honest so dont know.
Hi Mate,
I\'m running an apexi ecu, it\'s a road car that will see occasional drag and track my work permits. It would be nice if the stock mazda fuel pump resistor could be used as it sends 9volts to the pump at idle and low load and under high load it is bypassed and full voltage goes to to the pump.
Because i\'m not using the stock wiring for the bosch pumps I cannot utilise the stock fuel pump resistor, so next best method I could think of to minimise the negative affects of running full voltage to the pumps at all time was this fuel pump speed controller. I actually got a response back from aeromotive technician yesterday who said it is not advisable to run two pumps on one controller, so looks like i\'ll have to get two fortunately the wiring is very base and simple and their the size of a blackberry so shouldn\'t be too much iof an inconvenience. Thanks for your help and advise.
Oh fuel lines will be dash -6 from the pumps to a y connector and the -8 from the other side of the y connector through a inline filter to the fuel lines. I have not made up my mind for the return line i\'m still doing some reading up on this bit it will be either -8 or -10
rgds
Brian
The 30 Amp relay usually has a blow off at about 45 amps. going with a 40 amp will need 60 amps before it blows