LH Series

Up to 150kV  Regulated High Voltage DC Power Supplies

The LH family of power supplies are sophisticated, 5 kW, high voltage power supplies with low ripple and noise. They are air insulated, fast response units, with tight regulation.


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

  • Input:  187 – 264 V RMS, Three-Phase, 48-63 Hz, 6500 VA maximum at full load. Less than 20 A per phase at 208 VAC. A five-position rear terminal block with protective cover is provided. Mains service must be protected with fuses or circuit breakers with a maximum rating of 100 A for 200/208 VAC models & 60 A for 400 VAC models
  • Efficiency:Typically > 85% at full load.
  • Output:Continuous, stable, adjustment from 0 to rated voltage or current by panel mounted 10-turn potentiometers with 0.05% resolution, or by external 0 to 10 V signals is provided. Voltage accuracy is 0.5% of setting + 0.2% of rated.
  • Ambient Temperature:-20 to +40ºC, operating; -40 to +85ºC, storage.
  • Ripple: Better than 0.05% RMS of rated voltage at full load.


  • Arc Quench: The HV output is inhibited for a short period after each load arc to help extinguish the arc.
  • Arc Count: Internal circuitry constantly senses and integrates arcs that occur over a given time. In the event a system or load arcing problem develops and exceeds factory-set parameters, the power supply will cycle off in an attempt to clear the fault and then automatically restart after a preset “off dwell time”.
  • Pulse-Width Modulation: Off-the-line pulse-width modulation provides high efficiency and a reduced parts count for improved reliability.
  • Constant Voltage/Constant Current Operation: Automatic crossover from constant-voltage to constant-current regulation provides protection against overloads, arcs, and short circuits.
  • Constant Current/Current Trip: A rear panel switch allows selection of either current mode.
  • Redundant Thermal Overload Protection:Thermostats and fan RPM sensing shut down the power supply due to over temperature or reduced fan speeds.
  • Tight Regulation:Voltage regulation is better than 0.005% for allowable line and 0.01% for allowable load variations. Current regulation is better than 0.2% from short circuit to rated voltage.
  • Differentially Coupled Analog Control Signals: All voltage and current programming and monitoring signals are coupled to the user interface by true differential amplifiers. This provides for the ability to return the program and monitor commons to ground or system common at the source. This arrangement isolates the return wires and eliminates errors due to unwanted return currents flowing in these connections.

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Specifications Table

10.47 x 19.00 x 24.00 in (265.9 x 482.6 x 609.6 mm)
Input Voltage: 
187-264 VAC, 3 Phase or 340-460 VAC, 3 Phase
Up to 85%
Operating Temp: 
-20 to +40 °C
Worldwide Safety Approvals: 
EN61000-6-4:2007, Class A