Pulse-Width Modulation. Off-the-line pulse-width modulation provides high efficiency and a reduced parts count for improved reliability.

Air Insulated. The PK Series features "air" as the primary dielectric medium. No oil or encapsulation is used to impede serviceability, or increase weight.

Constant Voltage/Constant Current Operation. Automatic crossover from constant-voltage to constant-current regulation provides protection against overloads, arcs, and short circuits.

Current Trip. This feature may be substituted for constant-current operation by a jumper on the rear panel interface connector.

Tight Regulation. Voltage regulation is typically better than 0.01% for allowable line and load variations. Current regulation is better than 0.1% from short circuit to rated voltage.

Higher Power Capability. Power supply modules can be paralleled for 8 kW output power utilizing one master control module and one slave module.

Operating Parameters at a Glance Output voltage and current are displayed on separate 3 ½ digit LCD displays with selectable damping. Dual LED bar graphs provide "analog" indication of rapidly changing output level. A full set of indicators are provided to determine the status of the supply at a glance. These include indicators for AC power on, high voltage on, standby, safety interlock, external trip, output polarity, regulating mode (voltage or current) and remote control status of mA program, kV program, and HV enable.

Warranty. Standard power supplies are warranted for three years; OEM and modified power supplies are warranted for one year. A formal warranty statement is available.

(Specifications apply from 5% to 100% of rated voltage. Operation is guaranteed down to zero with a slight degradation of performance.)

Input: 4/8 kW, 3-phase: 187-228 V RMS, 48-63 Hz, fused for 20 A (per 4 kilowatt module), derate for line unbalance > 2%. 5-position terminal block, with cover, provided. 8 kW supplies have one additional terminal block for the slave.

Output: Continuous, stable adjustment from 0 to rated voltage/current by means of panel mounted 10-turn potentiometers with 0.05% resolution, or by external 0-10 V signals. Repeatability better than 0.1% of full scale. Accuracy is 1% of rated + 1% of setting

Voltage Regulation: Load, better than 0.01% for no load to full load variations; Line, better than ±0.01% over specified input range.

Current Regulation: Load, better than 0.1% +100 µA , from short circuit to rated voltage at any rated load condition; Line, better than better than ±0.01% over specified input range.

Ripple: Better than 0.1% RMS of rated voltage at full load up to 125 kV. Better than 0.05% RMS for 150 kV and higher.

Stability: 0.01% per hour after 1/2 hour warm-up; 0.05% per 8 hours.

Temperature Coefficient: 0.01%/°C.

Ambient Temperature: -20 to +50° C, operating; -40 to +85° C, storage.

Protection: Automatic current regulation protection reduces output voltage as required for all arc, overload and short circuit conditions. Fuses, surge-limiting resistors, and low energy components provide the ultimate protection.

Accessories: Detachable, 8 foot, shielded high voltage coaxial cable provided with fully enclosed models (see models chart for cable type). Enclosed 8 kW models are provided with an additional HV cable for the slave module. A 25 pin D-subminiature connector for customer interface is provided. Harness and/or interconnection cables supplied for 8 kW models as required.

Polarity: Available with either Positive, Negative, or Reversible polarity with respect to chassis ground.

Current Limit: In current limit mode the power supply will regulate the load current at the programmed current level with automatic crossover between voltage and current regulating modes.

Current Trip: A jumper installed on the 25 pin interface connector located on the rear of the control panel assembly allows the selection of current trip operation. When in current trip mode, the HV output will disable and latch off when the load current reaches the programmed current level. Reset is accomplished by either cycling the AC power, toggling the HV enable signal, or by pushing the HV off/reset and then the HV on switches.

Analog Monitors: Current and voltage, 0 - 10 V equivalent to 0 - rated output. 10 k ohm (1%), output impedance.

Voltage accuracy: 1% reading +1% of rated voltage. Current accuracy: 1% reading +0.05% of rated current.

Digital Monitor Signals: Four functions as follows - Milliampere Control, Kilovolt Control, High Voltage Enable, No Fault. High active, TTL or 5 V CMOS compatible. Typical signal compatibility; source = 1.0 mA at 2.5 V, sink = 2.5 mA at 0.4 V.

Digital HV On/Off Control:

HV Enable: Remote signal to activate high voltage (front panel switch selectable). High, on; low, off.
External: Remote signal to disable high voltage (overrides local or remote enable); High, disable. External has two user programmable modes; level-controlled interrupt or momentary-triggered shutdown.

Both inputs are TTL or 5 V CMOS compatible. Input is active upon application of 2.2 - 15 V signal. Approx.. input impedance: 100 k ohms @ 0 - 5 V; 10 k ohms @ 15 V.

External Interlock: Contact closure to common = enable; contact open = disable. Latching with reset via the HV off/reset switch or HV enable signal.

Opto-Output: An opto-isolated NPN transistor output is provided that can be controlled by any one of the Digital Monitor signals. This is not intended to be used for high potential isolation.

Front Panel Elements (See outline drawing)

AC Power: On/Off rocker switch and pilot lamp.
HV Enable: Momentary push-button and indicator.
HV Off/Reset: Momentary push-button and associated pilot lamps: Standby, Interlock, External.
Output Meters: Kilovolts, Milliamperes, 3 ½ digit LCD displays, accuracy 1% of full scale.
Output Controls: Kilovolts, Milliamperes, 10-turn with locking vernier dials.
Polarity: Indicators for positive or negative output with respect to ground.
Trend Indicators: 10 segment bar graphs to provide indication of rapidly moving output parameters
Mode Indicators: LED's for indication of regulating mode (voltage and current).
Remote Programming: Selector switches with indicators for remote/local selection of voltage, current, and HV enable.

Slave Front Panel Elements
(When applicable)

Indicators: Bias, Tracking, & Overvoltage.
Service Testpoints:
TP-I - Slave Current
TP-V - Slave Voltage
TP-C - Common

Rear Panel Elements (See outline drawing)

DS1: Power On indicator
E1: Chassis ground
F1, 2, 3: Input line fuses
J1: Customer interface connector
JHV1: HV Output connector
TB1: AC Input connector
TB2: Ground, Common, Interlock connector

Click on the model number below to request a quote and for complete ordering part number.

4 kW, Fully Enclosed

Maximum weight is 62 lbs. to 75 kV, 85 lbs. to 125 kV.

4 kW, Open Stack

Maximum weight is 125 lbs.

8 kW, Fully Enclosed (for models to 15 kW, consult factory)

Maximum weight is 125 lbs. to 75 kV, 170 lbs. to 125 kV.

8 kW, Open Stack

Maximum weight is 200 lbs.

Front Panel Controls & Indicators

Outline Drawing 3 - 75 kV

Outline Drawing 80 - 125 kV

Outline Drawing 150 - 400 kV