We have two versions of a simple potentiometer, a standard 10K linear pot with a 300′ arc, and a custom made 50° version. Both are rated at 1/4 W. These pots are plastic bodied with a plastic shaft so they have good water resistance. They are IP50 rated by the manufacturer (Omeg Ltd), and have a lifetime rating of >20 000 operations.
We consider these pots to be a bit like car brake pads, they have a spring loaded arm which presses on a carbon track, carbon is quite soft and will wear out if it is used a lot. A lot of intermittent control problems are solved by replacing the pot. We do stock a long life version, but these won’t work in the RBT throttle.
A standard 10K linear pot (10K ±20%) to suit all our controllers (except Porter 40). The shaft rotates through 300°. It has the same dimensions as the 50° pot below, but with solder tags rather than PCB pins.
Special 50° potentiometer
This is a pot made specially for 4QD: it is a ‘standard’ 10K (10K ±20%) linear pot (i.e. with 300° mechanical travel) but with the active resistive part of the track occupying only the centre 50° of the mechanical travel.
5K pot for Porter 40
A standard 10K pot can be used with the Porter 40 either by adding a 10K resistor in parallel, or by breaking a track on the board. Both are detailed in the Porter 40 manual.