Three Phase AC

Three Phase, Zero Cross:

The term Zero-Cross (synchronous operation of SCR's) is derived from the fact that the SCR's are turned on only when the instantaneous value of the sinusoidal wave is zero. In Zero-Cross operation, power is applied for a number of continuous half-cycles and then removed for a number of half-cycles to achieve the desired load power in the same manner as power would be controlled with a mechanical switching device. The frequency of the on-off cycles can be extremely fast because there is no limit to the number of switching operations the SCR can perform.

3 Phase, Phase Angle: 

In phase-angle control, each SCR of the back-to-back pair is turned on for a variable portion of the half-cycle that it conducts. Power is regulated by advancing or delaying the point at which the SCR is turned on within each half cycle. Light dimmers are an example of Phase-Angle control.

Model Phases Firing Mode Output Current Low Current High Highlights
MicroFUSION Three Phase Three phase Phase angle, Zero cross, Zero Cross Transformer Mode AC 8 400

MicroFUSION is an ultra-compact high performance digital SCR controller that adapts to the analog environment as well as the digital environment.

FUSION Three Phase (AC) Power Controller Three phase Phase angle, Zero cross, Burst AC 50 1 200

24 - 600 Vac. A microprocessor-based SCR controller operating both analog and digital interfaces. A phase angle or zero cross fired SCR controller which linearly controls, with respect to the setpoint, the AC voltage, current, or true power applied to a three phase electrical load. The 3 phase controller can be ordered in either 2 or 3 leg control with 2 leg being limited to zero cross firing. Control is achieved for 3 leg by three pairs of inverse parallel SCRs or in 2 leg by 2 pairs of inverse parallel SCRs.

Compact FUSION Three Phase Power Controller Three phase Phase angle, Zero cross, Burst AC 10 160

24 - 600 Vac. A microprocessor-based SCR controller operating both analog and digital interfaces. Can be ordered in either 2 or 3 leg control with 2 leg being limited to zero cross firing. Output is controlled linearly with respect to command signal and can be set to the average or RMS value of the voltage or current, as well as true instantaneous power or external feedback.

3629C Three Phase Power Controller Three phase Phase angle AC 50 1 000

208 - 575 Vac. Three Phase SCR Controller. Higher current ratings than our solid state relay models. Features include: current limiting, over-current trip, shorted SCR detection.

3337 Three Phase Zero Cross Power Controller Three phase Zero cross AC 200 750

208 - 575 Vac. Three Phase, Zero Cross SCR Controller. Accepts most commands. Features include: Sync-guard, Trans-guard, shorted SCR detection and on-board line fusing for most frame sizes.

3037 Three Phase Zero Cross Power Controller Three phase Zero cross AC 85 750

208 - 575 Vac. Analog SCR Controller. Accepts most commands. Features include: Sync-guard, Trans-guard, Shorted SCR detection and on-board line fusing for most frame sizes.

3027 Three Phase Power Controller Three phase Zero cross AC 85 750

208 - 575 Vac. Analog SCR Controller. Accepts most commands. Features include: Sync-guard, Trans-guard and on-board line fusing for most frame sizes.

3021B Three Phase Power Controller Three phase Zero cross AC 10 70

120 - 575 Vac. Analog SCR Controller. Accepts most commands. Sync-guard smoothes out line current draw when multiple controllers are in use.

3021A Three Phase Power Controller Three phase Zero cross AC 10 70

120 - 575 Vac. Analog SCR Controllers. Accepts most commands.

3020 Three Phase Power Controller Three phase Zero cross AC 10 70

120 - 575 Vac. Analog SCR Controller. Powered off of the 4/20mA loop, so no control transformer is required.

1600 (Multi-zone) Power Controller Single phase Phase angle, Zero cross AC 10 70

120 to 575 Vac. Multi-zone SCR Controller. Accepts most commands. Allows mixing of line voltages and load currents for multiple zones in a small footprint.