The GB4 Programmable Temperature Controller, basic model, is equipped with two Sending Units for use with Type K thermocouples. Additional Sending Units, Type S capabilities, key lock security and customized hardware and software are optional. These were developed at the behest of several of our customers. These variants are effected purely by means of software. You can do this yourself, so you do not have to send in your controller for service.
Some large kilns have trouble keeping a uniform temperature throughout.
Because of these considerations, some kilns are set up with independent banks of heating elements arranged into zones. Each zone has its own thermocouple and relay for its heating coils. If you want to heat the whole kiln uniformly, you would program the same temperature profile onto each channel and then start them all at the same time. The only sticky wicket in this scheme is the GB4 autohold function. If one zone goes into autohold mode, its timer stops advancing while the other zones timers do not.