EP1 - Single Phase SCR Power Control

Precise Single Phase Power Control

Phasetronics EP1 series of single-phase SCR power control features phase angle control to provide smooth proportional output power from 0-100%.The model EP1 was designed to make available low cost high quality SCR phase control.The EP1 series is available in load currents from 10 to 1000 amperes and at line voltages from 120 through 575 volts AC. These units are ideally suited for all resistive and inductive loads. A soft start feature assures a slow rising output voltage to prevent inrush currents on inductive loads. The standard soft start is active on power up and is reset after a power loss. Option S is available to provide soft start on input control signal change or lockout release. Lockout (external shutdown) can be activated by an external dry contact closure.

The control input is con??gurable to match all standard temperature and process controllers. The control signal sensitivity is adjustable by gain and offset potentiometers. The unit can also be controlled manually from an external potentiometer. MOVs protect the SCRs from voltage surges or transient voltages. False firing (dv/dt) protection is also included. I²T fuses are available as an option.Nema enclosures, circuit breakers, contactors and disconnect switches are available. Contact the factory for additional information.


AC Supply Voltage: 120 - 575 Vac

Amp Ratings: 10 to 1000 Amps

Control Signal: 4-20 mA, 0-10 Vdc, , 0-5 Vdc

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    External Inputs  
    Milliamp Input: 4-20 mA Input Impedance - 250 ohms
    Analog Input: 0-10 Vdc Signal / 0-5 Vdc Signal - 100k ohms input impedance
    Manual Control: 10k ohm, 2 watt potentiometer, linear taper (customer provided)

    Output Current Rating (Model dependent): 10 to 1000 Amps
    Output Stage: Back to Back configuration (AC Switch)
    AC Supply Voltage: 120/208/240/380/415/480/575 Vac (+10% to -15%, 50/60 Hz) *
    Type of Loads: Resistive / Inductive / Lamp
    Soft Start: Factory set for initial half-second of operation at power on. Field adjustable via potentiometer from 0.5 seconds to 20 seconds.
    Hard Firing Gate Pulse: A combination of a high-potential gate pulse and a rapid rise time is used to prevent SCR damage due to di/dt stress

    Input Adjustments  
    Gain: 4-20mA, 0-5 Vdc, 0-10 Volts
    Offset: 50% of gain maximum

    Regulation: Optional Feature to provide Average Load Voltage regulation of +/-2% over a +/-10 % line voltage input change.

    Protective Networks  
    Optional Fusing: IІT fuse protects against short-circuit overloads (Option F)
    Transient Voltage Suppressor: Integral MOV (Metal Oxide Varistor) protects against high potential transient voltage
    SCR Peak Inverse Voltage (PIV Rating): 1500V for all models.
    RC Snubber: RC snubber networks prevent false firing due to dv/dt characteristics

    Ambient Temperature: Operating range is from 0°C thru 40°C (32°F thru 104°F)