Under normal circumstances, relays will last many years even when the kiln is fired every day. It is not unheard of to hear about a relay failing, just not very common. If relays are failing often, usually there are other variables involved.
- The biggest contributing variable to why a relay would fail is the environment, specifically heat. If it gets hot in the kiln room, the relays will not last as long. If it gets really hot, the relays can fail quickly. Salt air compounds this problem too. Even just a fan pointing at the control box can help this.
- The next biggest contributing variable is a poor quality connection at the relay. This can take on a couple different forms. For example, if the relay overheats and fails and one of the wires got hot and was not replaced, that overheated wire can cause the next relay that is put in to overheat and fail too. It is important to replace anything else that has gotten hot when replacing a relay. Another example of a poor quality connection at the relay is using a standard rated wire terminal rather than a high temp rated wire terminal on the power wire connections to the relay. With all the amps running through that relay and considering that it is probably already hot to begin with around the relay, it is possible to have the connection between the wire to the relay to begin to heat up. A high temp terminal would be better able to withstand this heating.
- Cool off the room or at least cool off the control panel as much as you can.
- Check your wiring connections as noted above.
- The first thing to try is to lower the cycle time that the DynaTrol uses to control the contactors / relays. See how to change the cycle time here.
- Consider replacing with mercury relays if it is appropriate (i.e. if you are in a factory environment - NOT a school). Contact L&L if you wish to discuss this option.