The large mass inherent in a metal sheath electric radiant type heater permits the use of a pulsing type control. Unlike a quartz infrared heater which turns on or off quickly, a metal sheath heater takes about two minutes to reach its color temperature. When shut off, the metal sheath heater requires about the same amount of time to cool down to room temperature.

Because of this time lag, the metal sheath heater can be cycled to hold a predetermined temperature. A "percentage" input timer is used to control the on/off cycle. This timer has a solid state pulsing device with a 30 second cycle. The control dial is calibrated from 0% to 100%. By turning the dial, you can have your heater energized for any percentage of the 30 second cycle.

For example: To get 80% heater output, the timer is set to 80%, creating a cycle of 24 seconds energized and 6 seconds off. It would continue to operate at this cycle until manually changed.

Accessories for Metal Sheath Radiant Heaters

On-Board Transformer Eliminates Second Voltage Feed

A transformer is desirable to eliminate the need for feeding two voltages: one to the controls and one to the load. Before now, this would mean that three housings were needed to wire together the timer, the contactor and the transformer.

Now Aitken brings these three components in one dust-tight box with an on/off switch and pilot tight. It is completely pre-wired and requires only the three phase feed through the contactor. This makes for a neat, inexpensive, precise control, completely pre-wired for noninductive loads.