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You say track voltage, I say track current!
I hear a lot of discussion about track voltage when the basic wiring of the track is more important. Are the connections properly soldered? Is the wire of proper size? Is the charger any good (it is not an automatic charger is it). A comment about two separate power sources, one for each lane. This has been tried, the problem is that you can not get two battery set-ups to produce identical power curves. One lane WILL BE BETTER.
The battery type is best explained as follows. Large deep cycle batteries are designed to supply a small amount of current over a long period of time. Good examples of this include a fork lift, or a trolling motor. The fork lift needs a battery to last a least an average shift. The trolling motor needs a battery that will last all day, unless you live in Texas where you can catch your limit in no time flat <g>. The 8d battery on the other hand is designed to start a diesel engine with 30 weight oil, in -30 degree weather! This means a battery that can supply a large current spike to turn over the engine under these conditions. Basically larger plates equal a slower discharge rate, smaller plates equal a faster discharge rate.
With the current demand that we use in the grp 7 classes, this sounds like what we need for drag racing does it not? It is! Chargers also very a great deal. The automatic chargers turn themselves on as needed. Guess when this happens. That’s right buckaroo's after you launch the cars. This makes for a REAL treat in brackets! Manual chargers provide a steady charge rate to the batteries at all times and provide the steady current needed for consistent racing. A very simple test of the real track power can be done as follows. Take a high quality digital volt meter (Fluke, Beckman) and hook the test leads to the braid at the FINISH LINE. Do this were the taps hook up under the track at the point where the powered part of the lanes end.
Now have someone watch the volt meter and then run two cars down the track and observe the first voltage reading as the cars launch. Also watch how the track voltage rises as the cars travel down the track towards the finish line. The try the same test using only one car. The second test should produce the SAME READINGS, if not there are problems. The reading of the first spike on the meter at the cars launch should be within 3 volts of the reading taken directly from the battery posts. If not there are problems.
Why is this the correct method for testing track power. This method shows what the voltage is at the braid under load. It will show that there are problems with CURRENT FLOW which is what the motors need to operate. If you compare track current with water flow the terms can be summed up as follow. Voltage is pressure, amps are gallons per minute. 100 lbs. of water pressure in a 1/2" pipe will flow a set amount of gallons per minute. 100 lbs. of water pressure in a 2" pipe will flow a much greater amount of gallons per minute.
The same thing can be said of the wire size on a track. On the same note if the 2" pipe has leaks or blockage it will not flow the rated amount of water. Same deal with the current passing through wire. If the wire connections are not done properly, the rated amount of current will not pass through the wire.