a123 battery for ecu
01-12-2008, 01:37 PM
#2
My Feedback: (2)
RE: a123 battery for ecu
Hi Arden,
The motor comes stock with a 7.2 V pack. A 9.9 volt pack is within the ECU's operating limits, but there are two concerns.
(1) On a 7.2volt pack, the ECU draws somewhere in the vicinity of ~16 amps when the start is just initialised. This is just a peak amperage, occurring when the motor just makes contact with the compressor nut and becomes stalled out for an instant. the current drops off rather quickly once the shaft begins to rotate of course... You'll need to size a pack for that peak amperage + a few amps for tolerance of components and taking into account the increased driving voltage. I can't say exactly what will happen since I have no experience what so ever with this battery.
(2) You may wind up driving some components with a higher voltage, such as the starter motor and propane solenoid for example. The propane solenoid operates as if it is connected directly to the pack, and is not limited to a specific voltage. the solenoid is designed for a 6V driving voltage, but 7.2 does not seem to cause any long term effects. I can not state what you should expect if you try to run it at 9.9 V in the short or long term. The current will be far higher than the valve is accustomed to.
The only battery that I typically recommend that is a deviation from spec is the Duralite 7.4 V ECU pack, 3600mAh or more. I would need to test one for myself and discuss the results with PST in Thailand prior to qualifying this battery as a suitable alternative.
I'll also reply to your PM re: the fuel solenoid upgrade later today.
Kelly
The motor comes stock with a 7.2 V pack. A 9.9 volt pack is within the ECU's operating limits, but there are two concerns.
(1) On a 7.2volt pack, the ECU draws somewhere in the vicinity of ~16 amps when the start is just initialised. This is just a peak amperage, occurring when the motor just makes contact with the compressor nut and becomes stalled out for an instant. the current drops off rather quickly once the shaft begins to rotate of course... You'll need to size a pack for that peak amperage + a few amps for tolerance of components and taking into account the increased driving voltage. I can't say exactly what will happen since I have no experience what so ever with this battery.
(2) You may wind up driving some components with a higher voltage, such as the starter motor and propane solenoid for example. The propane solenoid operates as if it is connected directly to the pack, and is not limited to a specific voltage. the solenoid is designed for a 6V driving voltage, but 7.2 does not seem to cause any long term effects. I can not state what you should expect if you try to run it at 9.9 V in the short or long term. The current will be far higher than the valve is accustomed to.
The only battery that I typically recommend that is a deviation from spec is the Duralite 7.4 V ECU pack, 3600mAh or more. I would need to test one for myself and discuss the results with PST in Thailand prior to qualifying this battery as a suitable alternative.
I'll also reply to your PM re: the fuel solenoid upgrade later today.
Kelly
01-30-2008, 12:55 AM
#4
My Feedback: (2)
RE: a123 battery for ecu
Yeah, I know I've been a little late on that one. Sorry about that. I've been a bit sick, and out of town the last few days... Also, If you see the earlier [link=http://www.rcuniverse.com/forum/m_6988239/tm.htm]thread[/link], you'll notice that I'm officially not part of PST any longer. I'll answer this one for you though, since I promised you a reply. Further on, I'd suggest you contact the factory directly.
To answer why the engine would not get flooded with fuel, you should first ask why would it in the 1st place? The fuel solenoid is not required in that the ECU will not command the fuel pump to run until the necessary parameters have been met. Fuel will not move through the system in a significant flow rate if the pump is not running, and it won't flood in start up with the fuel pump following its pre programmed ramp curve... On the other hand, if you fill up your jet and forget to close the ball valve, you will likely have a heightened EGT due to the internal pressure causing some fuel to leak through the pump and drip into the engine case prior to the start up.
Kelly
To answer why the engine would not get flooded with fuel, you should first ask why would it in the 1st place? The fuel solenoid is not required in that the ECU will not command the fuel pump to run until the necessary parameters have been met. Fuel will not move through the system in a significant flow rate if the pump is not running, and it won't flood in start up with the fuel pump following its pre programmed ramp curve... On the other hand, if you fill up your jet and forget to close the ball valve, you will likely have a heightened EGT due to the internal pressure causing some fuel to leak through the pump and drip into the engine case prior to the start up.
Kelly
02-08-2008, 09:08 PM
#6
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RE: a123 battery for ecu
Ajay, PST should be able to help with your requirement. Please contact us direct.
Cheers,
Kraivuth S.
[email protected]
Cheers,
Kraivuth S.
[email protected]
05-02-2010, 03:25 AM
#7
RE: a123 battery for ecu
