Back to Technical Information Electrical Control Batteries Electrical WmegaTrac® wiring is the largest gauge in the industry. Primary wiring is #6 gauge. Battery leads are actually arc-welding cable. Battery connectors are 175 amp silver-plated. A 200-amp fuse is provided to protect against short circuits or careless servicing. Primary circuit breaker is 150 amps. The battery charger port is on the front panel. The motor controller is mounted on the powerbase with a remotely joystick housing that usually mounts on an armrest. An accessory 24-volt receptacle is provided for accessory power such as power seating. Chair movement under electrical power is inhibited when the battery charger is plugged in or when freewheeling is selected. It is also inhibited by powered seating when positioned outside safe operating positions Top of the Document Control TEFTEC®'s motor controller is made up of two channels, drive and steering. The drive channel is rated at 150 amps and the steering channel is rated at 100 amps although these are regulated down to the motors' capabilities. During a climbing steering turn, 200 amps are available. Due to the nearly absent friction of TEFTEC's transaxle, descending a hill will charge the batteries, using the drive motor as a generator. Up and down hills uses only a little more energy from the batteries as level ground. No electrical system is without loss, but the overall system in the WmegaTrac® is among the most efficient DC systems around. That coupled with the fully anti-friction-bearing transaxle with all parallel gears in the drive train, gives a very efficient package. You can get a sense of how efficient a drive train is by feeling the gearbox temperature after a wheelchair has climbed a long hill. The warmth is cause by energy that was not used to propel the chair, but to heat the gears. Worm gear drives are quiet but only about 35% efficient. Worm gearboxes usually can be identified by their shape. If the gearbox looks like it could contain a shaft about the size of your finger and a thick slide of tomato located like its rim is perched on the middle of your finger, it is likely a worm gearbox. If the motor shaft is at right angles to the wheel axle, it is likely a worm gearbox if the motor shaft is well above or below the output shaft. Top of the Document Batteries The battery that fits the WmegaTrac® is the MK brand M24SLDG. We are told that these are about 75 ampere-hour units. New batteries are only about 65% efficient and require 15 to 20 discharge-charge cycles to become 100% capable. Batteries must be charged at least once a week even if not in service. In service, it is better to charge them every night, or day, depending on the chair's idle time. Top of the Document