4 kW Regulated
DC Power Supplies
200 kV to 500 kV
Parallelable up to 20 kW
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Driver and Remote Panel
4 kW System
|The LH open stack family are
sophisticated 4 kW power supplies with extremely low ripple and noise. They
are air insulated fast response units with tight regulation.
Please refer to Technology > Applications page on our web site for typical
The LH Series, when configured with the 400 VAC input option, are fully compliant with the following European Directives:
• EN61010/ IEC61010, Safety
• EN61000-6-4, Conducted and Radiated Emissions
• EN61000-6-2:2005, Conducted and Radiated Immunity
Arc Quench. The HV output is inhibited
for a short period after each load arc to help extinguish the arc.
Arc Sensing. Internal circuitry constantly senses and integrates arcs
that occur over a given time. In the event that a load arcing problem develops,
the power supply will cycle off, then automatically restart.
Embedded Microcontroller Control. Integral RS-232, USB and optional
Ethernet communications provide remote control program and monitor.
Air Insulated. The LH Series features “air” as the primary dielectric
medium. No oil or encapsulation is used to impede serviceability, or increase
Low Ripple. Typically, ripple is less than 0.1% peak to peak of rated
voltage at full load.
Parallelable. One master supply and up to 4 slave supplies provide a
maximum of 12 - 20 kW depending on kV.
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 selector switch on the remote
chassis allows selection of either current mode.
Tight Regulation. Voltage regulation is better than 0.005% for allowable
line and load variations. Current regulation is better than 0.1% from short
circuit to rated voltage.
Warranty. Standard power supplies are warranted for three years; OEM and
modified power supplies are warranted for one year. A formal warranty statement
Specifications apply from 5% to 100% rated
voltage. (Operation is guaranteed down to zero voltage with a slight degradation
Input: 187-228 V RMS, 3Ø, 48-63 Hz, 5500 VA maximum at full load. Less
than 16A/Ø at 208 VAC. A five position terminal block with protective cover is
provided on the rear panel of the driver chassis. Mains service must be
protected with fuses or circuit breakers with a maximum rating of 125 A for
200/208 VAC models & 100 A for 400 VAC models.
Efficiency: Typically 80% 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. Repeatability better than 0.1% of setting. Voltage
accuracy is 0.5% of setting + 0.2% of rated.
Static Voltage Regulation: Better than +/- 0.005% for specified line
variations and 0.005% for no load to full load variations.
Current Regulation: Better than 0.1% from short circuit to rated voltage
at any load condition, when in current regulation mode.
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 or HV ON/OFF buttons or by toggling the HV enable signal. A
switch located on the rear panel of the remote control chassis allows the
selection of current limit or current trip operation.
Voltage monitor: 0 to 10 V equivalent to 0 to rated voltage. Accuracy,
0.5% of reading + 0.2% of rated. Impedance is 10 KΩ.
Current monitor: 0 to 10 V equivalent to 0 to rated current. Accuracy, 1%
of reading + 0.05% of rated. Reverse polarity models: 1% of reading + 0.1% of
rated. Impedance is 10 KΩ.
Stored Energy: Stored energy varies with output voltage and is tabulated
in the models chart.
Ripple: Ripple consists of two major components, inverter switching
frequency components and line frequency related components. The inverter
frequency component is dependent on the amount of load current drawn. The line
frequency related component is determined by the amount of power delivered to
the load. The maximum values for both components are specified in the models
Stability: 0.01% per hour after 1/2 hour warm-up, 0.05% per 8 hours.
Voltage Rise/Decay Time Constant: 400 ms typical using either the HV ON
switch or remote programming with a minimum 2.7 mA resistive load.
Temperature Coefficient: 0.01%/°C.
Ambient Temperature: -20 to +40° C, operating, -40 to +85° C storage.
Protection: Automatic current regulation protects against all overloads,
including arcs and short circuits. Thermal switches and RPM sensing fans protect
against thermal overload. Fuses, surge-limiting resistors and low energy
components provide ultimate protection.
Arc Quench: An arc quench feature provides sensing of each load arc and
quickly inhibits the HV output for approximately 0.25 seconds after each arc.
Arc Sensing: Internal circuitry senses the number of arcs caused by
external load discharges. If the rate of consecutive arcs exceeds approximately
one arc per second for 5 arcs, the supply will turn off for approximately 5
seconds to allow clearance of the fault. After this period the supply will
automatically return to the programmed kV value with the rise time constant
indicated. If the load fault still exists the above cycle will repeat.
RS232/USB/Ethernet Programming and Monitor Accuracy:
Resolution: 0.025% of full scale for both the voltage and the current
programs. 0.1% of full scale for both the voltage and the current monitors.
Remote setting accuracy: Voltage setting accuracy is better than 0.5% of
setting + 0.2% of rated.
Remote reading accuracy: Voltage reading accuracy is 0.5% of reading +
0.2% of rated. Current reading accuracy is 1% of reading + 0.1% of rated.
Remote Control Unit: A separate control panel chassis is provided which
contains all the control functions.
The front panel of this assembly contains: separate 10-turn controls with
locking vernier dials used to set the voltage and current levels, High Voltage
ON switch, High voltage OFF/Reset switch and an AC power on/off switch and
indicator. LED‘s indicate when the high voltage is on, output polarity,
interlock status, fault status, and whether the supply is operating in a voltage
or current regulating mode. Output levels are indicated by voltage and current
The rear panel of this assembly contains: AC Power On indicator, ground stud,
driver/control chassis interface connectors, current limit/current trip selector
switch, remote user interface connector and RS232/USB connectors.
The signals provided on the remote user interface connector are as follows:
Inputs: Output voltage and current program signals, and high voltage
Outputs: Output voltage and current monitor signals, a +10 V reference
source, a high voltage status signal, fault status, and V/I mode status.
Signal common and ground reference terminals are also provided.
Remote HV Enable: 0 - 1.5 V = OFF, 2.5 - 15 V = ON.
External Interlock: Open = off, closed = on. Latching with reset via the
HV ON switch. The front panel indicator is illuminated when the interlock is
open. Interlock connections are provided on a terminal strip on the rear panel
of the driver chassis.
Accessories: 25 feet of detachable interconnection cables, a 10 foot null
modem cable, and a 10 foot USB cable are provided.
||Zero start interlock. Voltage control, local or
remote, must be at zero before HV will enable.
||Slow start ramp. Specify standard times of 5,
15, 20, or 30 seconds ± 20%.
||0-5 V voltage and
||180-220 VRMS, 3Ø
input, 48-63 Hz.
||340-460 VRMS, 3Ø
input, 48-63 Hz. (Required for CE compliance.)
COM port over Ethernet network. (Requires compatible OS (eg Windows) for COM
|Please consult factory for
Click on the model number below to request a quote and
for complete ordering part number.
4 kW, Open Stack
8 kW, Open Stack
For Models Greater Than 8 kW, Please Consult
High Voltage Stack Assembly
Driver Assembly - Slave
Remote Control Assembly
8 kW System