The “WATTCOR W312” thyristor power controllers are designed to control:
– standard resistive loads with a low temperature coefficient,
– short, wave infrared heaters.
– Inductive loads, transformer primaries
They can be used in the following cases:

• Single-phase: connection of the load and instrument between 2 phases or between one phase and Neutral.
• Three-phase: use of three W312 open delta or star connected with neutral.

The W312 series is designed on the basis of a common architecture, whose dimensions are defined by the five different current load specifications for a room temperature of 50°C. The power circuit has been designed to operate under a wide range of voltage.
The working voltage can vary from a minimum of 24Vac to a maximum of 660Vac (Max. range 20….725Vac). The operating principle is phase angle firing. With this type of switch-on, the load power control is performed by slicing the individual half-waves.
The conduction angle varies in proportion to the analog control signal so that power can be adjusted from 0 to 100%. The voltage control signal (0…5V or 0…10V) or current control signal (0/4…20mA) is nor-mally supplied by a temperature controller or directly from a potentiometer (manual control.
The phase angle switching device guarantees precise power control and adequate switching speed, which also permits use of the soft-start function. The soft-start function introduces a power ramp when the auxiliary power supply is switched on.
The conduction angle varies from zero up to the value corresponding to the control input in a set time. This function is indispensable with resistive loads at low resistance when cold (tungsten, molybdenum dislicide, kanthal super).
A logic input can be used to inhibit the power controller interrupting, where necessary, the power delivery, notwithstanding the presence of the command signal.
The LED indicators on the front indicate:

• the presence of the electronics auxiliary supply voltage;
• the conduction status of the instrument. WATTCOR W312 products are designed to guarantee rated current and tension values at a room temperature of 50°C. Working range is -5°C to 60°C. Signal connectors are “plug-in” type for easy wiring. The product can be installed either on the DIN bar or on the front panel.