EUROTHERM has released the 7100S range of single phase, solid state contactors. They offer cost-effective, robust power control for switching of resistive loads. They are available for loads up to 250A and voltages up to 500Vac.
The contactors are designed for use either with simple resistive (LTCL) or short wave infrared (SWIR) loads. Current ratings now extend from 16A to 250A. Applications include furnaces, plastic injection and extrusion, heating, and air-conditioning. The units are designed to replace electromechanical power relays. They can provide alarm and diagnostic information such as SSR fail, load fail, or diagnostic (partial) load failure options and can accept dc or ac logic inputs, as well as 4mA-20mA signals.
Two firing modes of the 7100S are available. Standard on/off with zero voltage switching and fast cycle firing. Fast cycle firing mode allows the 7100S to operate in burst mode. In this mode the on and off times are determined as a proportion of the input signal. This provides tighter control of the amount of energy being delivered to a process, while retaining the benefits of zero voltage switching.
Unlike electromechanical relays the 7100S is solid state, with no moving parts. It provides completely silent operation and never wears out, providing trouble-free operation for the life of the project. It can also operate at much higher speeds than an electromechanical relay. The use of on/off logic firing with zero voltage switching provides no electrical interference to the system.
The 7100S is available with DIN rail or panel mounting. It is provided with an integral heatsink allowing for quick and easy installation, plus a fuse and fuse holder for immediate operation. Versions are available in voltages from 110V up to 500V. LED indication of firing is provided for confirmation of operation.
They are designed for use in industrial applications. Robust thyristors are utilised in place of triacs with extra MOV and RC protection for protection against surges and overload. The power switching elements are thyristors, providing improved protection against damage due to surges. Typical surge ratings are around 1400V. They are fully rated to the design’s maximum operating temperature of 45°C.
All units are manufactured within ISO9001 certified production environments and are designed to comply with all relevant international standards. This includes CE in Europe and UL in Canada and the USA.