Watlow Australia have introduced the NO-ARC relay technology which can be incorporated into several new high-profile products including E-SAFE II hybrid power switch, EZ-ZONE PM integrated controller and EHG SL10 process controller and safety limit.
Standard relays typically consist of two separate and independent circuits. The first (a coil) drives the electromagnet. When the switch is on, the electromagnet is switched on and attracts the armature. The armature acts as a switch in the second circuit (the contacts). When the electromagnet is energised, the armature completes the second circuit. Standard relays can experience arcing or surges in current. When an arc jumps across the contacts, it can melt a small section of the contact surface and contacts can weld together.
The NO-ARC relay is a mechanical relay with arc suppression provided through the use of smart electronics. The technology reduces the amount of arcing across the relay contacts thereby extending the life of the relay. The arc suppression is essential to effectively manage thermal properties and provide a switch with a long life. Relays without NO-ARC typically have a life cycle of about 100,000 cycles at rated amperage, while the NO-ARC relay will have a life of more than four million cycles.
Watlow Australia's products that have incorporated NO-ARC technology include:
E-SAFE II Hybrid Power Switch- E-SAFE II provides reliable and accurate power switching in a mercury-free product. E-SAFE II offers a switching life of millions of cycles at 35 amperes at an ambient temperature rating of 70°C (158°F). NO-ARC technology allows it to switch millions of cycles while decreasing noise and increasing temperature accuracy. The switching mechanism of Watlow's E-SAFE II is a hybrid solid state and mechanical relay. This allows faster cycling and more precise control.
EZ-ZONE PM Integrated Controller- The EZ-ZONE PM is a 1/32 or 1/16 DIN panel mount controller offering options to reduce the complexity and cost of a control loop. The EZ-ZONE PM controller can be configured as a PID controller, over/under limit controller or these functions can be combined and used as an integrated controller. Using NO-ARC relay technology the EZ-ZONE PM is able to offer 15 ampere load capacity and offers over two million cycles at rated load (maximum 240V~(ac), five second minimum cycle time).
EHG SL10 Process Controller and Safety Limit- EHG SL10 is an integrated/adjustable, temperature controller and heater all in one system. EHG SL10 incorporates a NO-ARC relay as the process output switching device thereby making it reliable. This controller will provide four to five million cycles at 10 amp rating.