TripTek Question

boulderado · 07-07-2007, 02:11 PM

Does anyone know how the TripTek computer calculates fuel mileage. Does it take into account what the generator uses?

Thanks.

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boulderado · 07-07-2007, 02:11 PM

Does anyone know how the TripTek computer calculates fuel mileage. Does it take into account what the generator uses?

Thanks.

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CalTex · 07-07-2007, 04:24 PM

Good question, I have wondered that myself. My guess is that it doesn't.

SargeW · 07-07-2007, 08:15 PM

With all the electronics in the rigs these days, nearly all functions are controlled by computers. The fuel mileage is usually estimated by a throttle position sensor built into the engine control module (ECM). I have an add on engine monitoring system made by a company called Silverleaf. The product is a VMSpc and runs on a loptop in the front of the rig. It plugs into the engine data port under the dash. Many functions, including mileage are displayed via the vehicle ECM. Your trip tech is very similar. So your guess is correct. The Trip Tech will have no idea how much fuel your generator uses. The way I estimate how much fuel the generator uses is to note the hour meter on the generator before I start it up. I use about 1/2 gallon per hour at half throttle on the generator, as per the Onan manual. It's not perfect, but it gives me a rough idea if I am monitoring my mileage on the MH. For the Trip Tech to monitor the fuel used by the generator, it would have to be hooked up to the mechanical fuel gauge in the tank. Hope this answers your questions.

Sarge

C Zimm · 07-08-2007, 02:17 PM

As I understand it "my TripTec calculates MPG for the engine only". It has no connection with the generator or it's fuel use.

vicsryd · 07-08-2007, 07:08 PM

That is correct. And since it's reading is based solely on the ECU fuel map a given throttle/load I find it's not very accurate even if the generator isn't a factor. For me on paper I get about 1/2 mpg better (e.g. 7.5 mpg) than what Trip Tek reports (7 mpg) for a leg with no generator use.

kellysrv · 07-09-2007, 10:32 AM

I also don't think the Triptek monitors generator fuel usage, it does however monitor run time on the generator for a handy notification of maintenance. I have found the Triptek MPG readings to be pessimistic most of the time, that is, I can never fill the tank with the number of gallons it says were used since last fill. I am typically getting 0.4 to 0.5 mpg better with no generator usage. I find the generator (7500 watt) uses about 0.33 gph and figure that into true MPG calculations when i have considerable generator usage on a single fill of fuel.

Cruzer · 07-10-2007, 04:10 AM

Your TripTek is connected to the J1939 high speed data buss. This data buss serves the engine and transmission ECMs but does not interface with the generator set, which has no data buss. It has no way of knowing what the generator is doing, therefore the genset's fuel usage will need to be manually added in if you want accurate calculations.