DEI PVX-4130 User manual

DIRECTED ENERGY, INC.
PVX–4130
±6,000V Pulse Generator
OPERATION MANUAL
SERIAL NUMBER:________________
DATE:__________________________
Directed Energy, Inc.
2401 Research Blvd., Ste. 108
Fort Collins, Colorado 80526
970/493-1901 FAX [phone]
SI Scientific Instruments GmbH ... the better technology
Roemerstr. 67 | 82205 Gilching/Germany | Phone: [phone] | E-mail: [email protected] | Web: www.si-gmbh.de

DEI PVX–4130
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TABLE OF CONTENTS
1.0 GENERAL DESCRIPTION ..........................................................................3
2.0 SPECIFICATIONS.......................................................................................4
3.0 SAFETY.......................................................................................................5
3.1 Operating Safety Summary...............................................................5
3.1.1 Power Source......................................................................5
3.1.2 Grounding............................................................................5
3.1.3 Cover Removal....................................................................5
3.1.4 General Operating Precautions...........................................5
3.2 Servicing Safety Summary................................................................6
3.2.1 Servicing Procedure............................................................6
3.2.2 Internal Energy Storage.......................................................6
4.0 OPERATING CONSIDERATIONS...............................................................6
4.1 Output Cabling..................................................................................6
4.2 Load Simulation ................................................................................7
4.3 Trigger Input......................................................................................7
4.4 Pulse Voltages +V IN and -V IN........................................................7
4.5 Output Pulse Considerations.............................................................7
4.6 Controls and Indicators .....................................................................8
4.6.1 Power Switch and LED........................................................8
4.6.2 Output Switch and LED.......................................................8
4.6.3 Gate Connector...................................................................8
4.6.4 Gated LED...........................................................................8
4.6.5 Over Current LED................................................................9
4.6.6 Control Error LED................................................................9
4.6.7 Current Monitor....................................................................9
4.6.7 Voltage Monitor ...................................................................9
5.0 PREPARATION FOR USE ..........................................................................9
5.1 General .............................................................................................9
5.2 Initial Inspection ................................................................................9
5.3 Electrical Installation..........................................................................10
5.3.1 Input Power Cord.................................................................10
5.4 Electrical Check ................................................................................10
5.4.1 Power-Up ............................................................................10
6.0 OPERATING INSTRUCTIONS....................................................................11
6.1 Power-Up Procedures.......................................................................11
6.2 Power-Down Procedures ..................................................................12
7.0 TROUBLESHOOTING.................................................................................12
7.1 Troubleshooting Procedures.............................................................12
7.1.1 Fuses...................................................................................13
7.2 Factory Service.................................................................................13
8.0 SYSTEM FAILURE MODES........................................................................13
8.1 Over-Current Failure .........................................................................14
9.0 WARRANTY ................................................................................................14

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********** WARNING **********
SAFE OPERATING PROCEDURES AND PROPER
USE OF THE EQUIPMENT ARE THE
RESPONSIBILITY OF THE USER OF THIS
SYSTEM.
Directed Energy, Inc (DEI) provides information on its
products and associated hazards, but it assumes no
responsibility for the after-sale operation and safety
practices.
ALL PERSONNEL WHO WORK WITH OR ARE
EXPOSED TO THIS EQUIPMENT MUST TAKE
PRECAUTIONS TO PROTECT THEMSELVES
AGAINST POSSIBLE SERIOUS AND/OR FATAL
BODILY INJURY. DO NOT PERFORM INTERNAL
REPAIR OR ADJUSTMENTS UNLESS ANOTHER
PERSON CAPABLE OF RENDERING FIRST AID
AND RESUSCITATION IS PRESENT.

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1.0 GENERAL DESCRIPTION
The DEI PVX-4130 pulser is a high voltage solid state pulser designed to
drive capacitive loads such as acceleration grids and deflection plates.
The PVX-4130 will generate an output voltage swing of 6000 volts, and output
current of 30 amperes peak and 0.1 amperes continuous. It produces very flat
voltage pulses to DC into a capacitive load.
The PVX-4130 Pulser can generate single-ended output pulses from ground
to +6000V or from ground to -6000V, and can also generate pulses
originating from a voltage offset from ground. This offset can be from -6000V
to +6000V, with a maximum power supply voltage differential (Vhigh - Vlow)
≤6000V.

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2.0 SPECIFICATIONS
All specifications are measured into a 50pF load connected with 4 feet (~1.2m) of RG-58 (50Ω) coaxial cable
INPUT DC VOLTAGE +V IN (Vhigh)
Source External
Absolute Maximum Value +6000 volts
Absolute Minimum Value -6000 volts
Relative Maximum Value +6000 volts over Vlow voltage
Relative Minimum Value Vlow voltage
Input Connector Kings 10KV, Rear Panel (+V IN)
Maximum Input Power 100 Watts (VHIGH + VLOW
supplies)
INPUT DC VOLTAGE -V IN(Vlow)
Source External
Absolute Maximum Value +6000 volts
Absolute Minimum Value -6000 volts
Input Connector Kings 10KV, Rear Panel (-V IN)
OUTPUT PULSE VOLTAGE
Maximum Value ±6000 volts (VHIGH - VLOW)
Minimum Value 0 volts
Means of Adjustment Controlled By Power Supply Input
Voltages
Output Connector Kings 10KV, Rear Panel
(OUTPUT)
GATE
Gate Source External
Gate Input +5V ±1V into 50Ω
Gate Rise Time <20ns
Gate Input Connector Type BNC, Front Panel
OUTPUT PULSE ELECTRICAL CHARACTERISTICS
(50pF load at end of 4 ft. RG-59 cable, 6000V)
Pulse Rise and Fall Time <60ns (10%-90%)
Pulse Width <150ns to DC, controlled by input
gate
Pulse Recurrence Frequency Single Shot to 10KHz, controlled
by input gate (1)
Droop <1% into a capacitive load
Maximum Duty Cycle Continuous
MONITOR OUTPUTS
Voltage Monitor (V Mon) 2kV/V Into 1 MegΩ
Current Monitor (I Mon) 10A/V Into 50Ω
These specifications are measured driving a 50pF load connected with 4 feet of RG-58 cable, at 6000V output. However
the PVX-4130 can drive loads of a few picofarads to several hundred picofarads of capacitance, limited by its maximum
power dissipation capability(1) . At lower load capacitances and/or voltages less then 6000V, the PVX-4130 can operate at
continuous pulse recurrence frequencies above 10KHz. The PVX-4130 can also drive resistive or inductive loads, within
limitations. Contact DEI for additional information and applications assistance.
(1) The power dissipated in the PVX-4130 when driving a capacitive load is defined by the formula CV2F, where C is the
total load capacitance, including the capacitance of the load, interconnect cable, and the internal capacitance of the PVX-
4130, V is the pulse voltage, and F is the pulse repetition frequency (or the total pulses per second). (For these
calculations, the internal capacitance of the PVX-4130 is 100pF, and RG-58 cable is 30pf/foot.) Given the maximum
dissipation of 100W, the maximum load capacitance, frequency and/or voltage at which the PVX-4130 can operate can be
approximated using this formula. This formula also approximates the high voltage power supply requirements needed to
drive a given load at a specific voltage and frequency. This formula is not applicable when driving resistive or inductive
loads.

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3.0 SAFETY
The high voltage of this device dictates the use of caution when operating or
servicing this equipment. The following is a summary of general safety
precautions that must be observed during all phases of operation and repair
of the PVX-4130.
3.1 Operating Safety Summary
The safety information contained in this summary is for both operating and
servicing personnel. Specific warnings may be found throughout this manual,
but may not appear in this summary.
3.1.1 Power Source
The PVX-4130 is designed to operate from a power source that will not apply
more than 240 volts AC between the supply conductors or between either
supply conductor and ground.
A protective grounding connection by way of the grounding conductor in the
AC power cord is essential.
3.1.2 Grounding
The PVX-4130 is grounded through the grounding conductor of the AC power
cord. To avoid electrical shock, plug the PVX-4130 into a properly wired
receptacle before making connection to any input or output connectors.
Use only a power cord that is in good condition.
3.1.3 Cover Removal
To avoid personal injury, do not remove the covers. Do not operate the PVX-
4130 while the covers are removed. The covers do not contain a safety
interlock!
3.1.4 General Operating Precautions
Do not remove the input or output cables while the pulser is in operation.
Never short-circuit the output of the unit. Failure to observe these precautions
can result in potential electric shock to personnel, arcing, and damage to the
connectors and system.
The top cover of the PVX-4130 is not safety interlocked. Extreme caution
should be exercised when removing the cover.

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Any pulsed power system is capable of random triggering via transients.
Therefore when the PVX-4130 is turned on, or dangerous voltage is present
in the chassis, assume it is possible to get a pulse on the output connector.
3.2 Servicing Safety Summary
The PVX-4130 contains dangerous voltages and stored energy. DEI strongly
recommends that all repairs and adjustments be performed by factory
qualified personnel. DEI will not be responsible for personal injury or damage
to the driver that occurs during repair by any party other than the factory.
3.2.1 Servicing Procedure
Do not perform internal repair or adjustments unless another person capable
of rendering first aid and resuscitation is present.
3.2.2 Internal Energy Storage
The PVX-4130 contains capacitors that are used as energy storage elements.
When charged, these capacitors contain approximately 3 Joules of stored
energy. This is sufficient energy to cause serious injury. Assure that the AC
power cord is disconnected from the driver. Verify that the capacitor
bank is fully discharged, and verify with a voltmeter that all circuits are
de-energized before servicing. The voltmeter used to make these
measurements must be certified for use at 6000VDC and 240VAC or greater.
Dangerous voltages, floating ground planes and energy storage exist at
several locations in the PVX-4130. Touching connections and/or components
could result in serious injury.
4.0 OPERATING CONSIDERATIONS
4.1 Output Cabling
The PVX-4130 is designed to drive capacitive loads with fast rise times. Since
the current out of the GRX is limited, the lower the capacitance, the faster the
rise time. Given fixed load characteristics, only the interconnecting cable type
and length will vary the output capacitance.
The unit is supplied with a 4-foot length of Teflon-insulated RG-58 coaxial
cable which has a capacitance of 30pF per foot. The unit is series terminated
in the characteristic impedance of this cable, which is 50Ω. DEI recommends
that the shortest length of cable possible be used to ensure the fastest
possible rise times and best pulse fidelity.

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4.2 Load Simulation
This unit was tested with a 50pF capacitive load connected to the output with
4 feet of RG-58 coaxial cable.
4.3 Trigger Input
An input trigger of +5V ±1V into 50Ωwith a rise time of <20ns is required to
gate on the PVX-4130. Departure from these values can result in a loss of
performance. These trigger requirements are met by any high quality low
voltage pulse generator. The trigger should be set to +5V ±1V into 50Ωbefore
the trigger cable is attached to the PVX-4130 trigger input. The input trigger
amplitude should be set using a 50Ωload (e.g. a 50Ωscope input) before
connecting it to the PVX-4130. If the trigger input is greater than +5V into 50Ω
, pulse stretching can occur.
4.4 Pulse Voltages +V IN and -V IN
The PVX-4130 Pulser is rated at a maximum pulse output voltage of
±6000VDC. Proper precautions should be taken by the user to ensure that
the maximum voltage is not exceeded.
4.5 Output Pulse Considerations
The PVX-4130 Pulser can generate single-ended output pulses from ground
to +6000V or from ground to -6000V, and can also generate pulses
originating from a voltage offset from ground. This offset can be from -6000V
to +6000V, but the maximum power supply voltage differential (Vhigh - Vlow)
should never exceed 6000V. The Vhigh supply should always be equal to or
greater than the Vlow supply, but never greater than 6000V above the Vlow
supply. Therefore the Vlow supply may be set to any voltage between -6000V
and +6000V, and the Vhigh supply may be set to any voltage between -
6000V and +6000V, but the voltage difference between Vlow and Vhigh
should never exceed +6000V. If the unit is operated with a single power
supply (i.e. single-ended), the unused power supply input should be
grounded.
When the input gate is high, the Vhigh supply is connected to the output.
When the input gate is low, the Vlow supply is connected to the output.
Therefore the PVX-4130can be used to generate a negative-going pulse by
logically inverting the input gate, so that the input gate is high until the unit is
pulsed. When the input gate goes low, the Vlow supply is connected to the
output, thereby generating a negative going pulse (see the example in the
figure below).

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4.6 Controls and Indicators
4.6.1 Power Switch and LED
The switch labeled "POWER" controls all AC power in the chassis. The
LED also labeled “POWER” above the switch illuminates when AC power
is turned on.
4.6.2 Output Switch and LED
The output switch enables and disables the pulse output. When the switch
is on, the output is enabled, and the "OUTPUT ENABLED" LED above the
switch is illuminated.
4.6.3 Gate Connector
The BNC connector labeled "GATE" is the input to gate the pulser. The
input should be +5V into 50Ω, with a rise time less than 20ns. The output
pulse width and frequency are controlled by the input gate's width and
frequency.
4.6.4 Gated LED
The LED labeled "GATED" illuminates when a gate signal of the
appropriate amplitude and width to gate the pulser is received. If the
"GATED" LED is not illuminated, the PVX-4130 will not generate an output
pulse.
Input Gate:
+5V
Ground
Output Pulse:
V
high
V
low
Generating a Negative Pulse with the GRX

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4.6.5 Over Current LED
The LED labeled "OVER CURRENT" illuminates if the output pulse current
exceeds 15A. If this LED illuminates, the pulse output will be inhibited for
6-7 milliseconds. If the LED illuminates continuously, the cause of the over
current fault should be corrected before attempting to operate the pulser.
4.6.6 Control Error LED
The LED labeled "CONTROL ERROR" illuminates if the input gate
frequency exceeds 10KHz. If this LED illuminates, the pulse output will be
inhibited. If the LED illuminates, reduce the frequency of the input gate
before attempting to operate the pulser.
4.6.7 Current Monitor
The BNC connector labeled "I MON" provides a 10A/V monitor of the
output current. This monitor should be terminated into 50Ω, such as the 50
Ωinput of an oscilloscope.
4.6.7 Voltage Monitor
The BNC connector labeled "V MON" provides a 2kV/1V monitor of the
output current. This monitor should be terminated into 1 MegΩ, such as
the 1 MegΩinput of an oscilloscope.
5.0 PREPARATION FOR USE
5.1 General
After unpacking, initial inspection and preliminary electrical check procedures
should be performed to assure that the unit is in good working order. If it is
determined that the unit is damaged, the carrier should be notified
immediately. Repair problems should be directed to the service department,
Directed Energy, Inc. (DEI), Fort Collins, Colorado. Telephone:
[phone].
5.2 Initial Inspection
1. Inspect unit for exterior mechanical damage.
2. Inspect power input cord and input power module for obvious signs of
damage.

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5.3 Electrical Installation
Standard units are shipped ready for use with a nominal 110-240VAC input.
5.3.1 Input Power Cord
The input power cord terminates externally in a three-prong polarized plug.
The unit chassis is wired to the plug through the line cord, and therefore, the
insertion of the plug into a compatible receptacle, hooked up to a grounded
input, will automatically ground the unit. The unit should not be operated
without a grounded AC input!
5.4 Electrical Check
Before proceeding, please review the precautions in Section 3.
5.4.1 Power-Up
The unit should be powered up using the following procedures:
1. Before connecting the pulse generator to the PVX-4130, set up the pulse
generator output to deliver a +5V pulse (±1V) into 50Ω, with a rep rate of
approximately 500Hz, and a pulse width of 1µs.
2. Connect the positive output power supply to the rear panel connector
labeled +V IN. Connect the negative output power supply to the rear panel
KING’S 10KV connector labeled -V IN. For +6000V single-ended output, -
V IN must be connected to ground. The power supply input should be
grounded if no power supply is connected. Ensure that both power
supplies are turned off.
3. Plug the power cord into the AC power input and turn on the front panel
Power switch. The "POWER" indicator LED should turn on, indicating that
the PVX-4130 is operational. If this does not occur, unplug the unit from
the AC power, and refer to the Troubleshooting Section of this manual.
4. Connect the pulse generator to the front panel BNC connector of the PVX-
4130 labeled "GATE".
5. Connect an appropriate load to the rear panel output connector.
6. Monitor the voltage at the output, by connecting one end of a coax to the
“V MON” BNC connector on the front panel and the other end to an
oscilloscope with a 50Ωterminator.

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7. Slowly turn up the high voltage power supplies. The PVX-4130 should
produce an output pulse, with a pulse width and pulse recurrence
frequency following that of the incoming trigger.
8. If there is no output from the PVX-4130, or the output is severely distorted,
turn OFF the high voltage power supplies. Leave the PVX-4130 connected
to the AC input without pulse voltage and with all connectors in place for
approximately five minutes to bleed off the stored energy, then disconnect
the AC power to the unit and refer to the Troubleshooting Section of this
manual.
6.0 OPERATING INSTRUCTIONS
This section provides basic operating instructions for the PVX-4130.
Additional application information may be found in Section 7.0.
WARNING
1. To avoid personal injury, do not remove the covers. Do not operate the
PVX-4130 while the covers are removed. The covers do not contain safety
interlocks!
2. Do not remove the input or output cables while the driver is in operation.
The PVX-4130 offers limited protection against shorts and arcs to ground,
however never intentionally short-circuit the pulse voltage output of the
pulser. If allowed to operate into a short for an extended period of time,
damage to the unit, load and/or associated cabling may result. Failure to
observe these precautions can result in potential electric shock to
personnel, arcing, and damage to the connectors and system.
3. Pulsed power systems are capable of random triggering via transients and
therefore when the PVX-4130 is turned on, or voltage is present in the
chassis, assume it is possible to get a pulse on the output connector.
6.1 Power-Up Procedures
The unit should be powered up using the procedures detailed in Section
5.3.1. When this is accomplished, the driver can be adjusted for the particular
application through the following procedure:
1. Monitoring the output of the PVX-4130 on an oscilloscope using the
internal voltage monitor or a high voltage probe connected to the output
load, set the output amplitude of the PVX-4130 to the desired level by
adjusting the output voltage of the high voltage power supplies.

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2. Set the output pulse width and pulse recurrence frequency by varying the
controls of the input pulse generator. The output pulse width should be set
by monitoring the output of the PVX-4130. The output pulse voltage will
follow the input trigger, but will not replicate in time the exact duration of
the input trigger due to asymmetric system propagation delays.
6.2 Power-Down Procedures
1. Set the high voltage power supplies to zero.
2. Turn off the high voltage power supplies.
3. Turn off the PVX-4130 power switch.
4. Disconnect the AC power to the unit.
7.0 TROUBLESHOOTING
WARNING
The PVX-4130 contains capacitors that are used as energy storage elements.
When charged, these capacitors contain approximately 3 Joules of stored
energy. This is sufficient energy to cause serious injury. Assure that the AC
power cord is disconnected from the driver. Verify that the capacitor
bank is fully discharged, and verify with a voltmeter that all circuits are
de-energized before servicing. The voltmeter used to make these
measurements must be certified for use at 6000VDC and 240VAC or greater.
Dangerous voltages, floating ground planes and energy storage exist at
several locations in the PVX-4130. Touching connections or components
could result in serious injury.
7.1 Troubleshooting Procedures
Before attempting to service or troubleshoot the PVX-4130, review the
servicing safety summary in Section 3.0.
The power MOSFETs utilized in the PVX-4130 are mounted on the printed
circuit board. In the unlikely event that the MOSFETs need be replaced, it is
highly recommended that the unit be returned to the factory for servicing.
The table below summarizes potential problems and their solutions. If these
recommendations do not resolve the problem, DEI customer service can be
contacted for further assistance.

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SYMPTOM SOLUTIONS
"POWER" LED Does
Not Illuminate •AC power not plugged in.
•Fuse(s) are blown. See fuse replacement
instructions in Section 7.1.1
No Output Pulse •No input trigger
•Input trigger voltage too low
•Input trigger pulse width too short. Increase
width.
•Input trigger frequency too high. Reduce
frequency.
•No high voltage. Check power supplies
•Output not connected correctly. Check all
cables and connections.
•Pulser is damaged. Contact DEI customer
service.
7.1.1 Fuses
To avoid fire hazard or damage to the driver, use only the fuse type listed on
the rear panel. Fuse replacement should be performed by qualified personnel
only. Assure that the AC power cord is disconnected from the driver.
7.2 Factory Service
If the procedures above fail to resolve an operational problem, please contact
the factory for further assistance:
DIRECTED ENERGY, INC.
2401 RESEARCH BLVD SUITE 108
FORT COLLINS, CO 80526
[phone]
FAX [phone]
8.0 SYSTEM FAILURE MODES
The PVX-4130 is capable of generating large amplitude current pulses with
very fast rise and fall times. There is limited over-current or over-voltage
protection circuitry, and it is the user's responsibility to assure that the
interconnect cables and load do not create transients, over-current or over-
voltage conditions that could damage the PVX-4130. FAILURE TO DO SO
VOIDS THE WARRANTY.

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8.1 Over-Current Failure
When the output is shorted, the PVX-4130 can deliver in excess of 30A of
current (depending on cabling, pulse power supply setting, etc.). A current
pulse of this magnitude is in excess of the driver's specifications. The PVX-
4130 offers limited protection against shorts and arcs to ground, however if
allowed to operate into a short for an extended period of time, damage to the
unit, load and/or associated cabling may result.
9.0 WARRANTY
There are no warranties, express or implied, including any implied warranty of
fitness for a particular purpose nor any IMPLIED WARRANTY OF
MERCHANTIBILITY made by Directed Energy, Inc. (DEI) except as follows:
DEI warrants equipment manufactured by it to be free from defects in
materials and/or workmanship under conditions of normal use for a period of
one year from the date of shipment to the purchaser. DEI will repair or
replace, at DEI's option, any product manufactured by it which is shown to be
defective or fails to perform within specifications within one year from the date
of shipment to the purchaser. OEM, modified and custom items of equipment
are similarly warranted, for a period of ninety (90) days from date of shipment
to the purchaser.
Equipment claimed to be defective must be returned, transportation prepaid,
to DEI's factory in Fort Collins, Colorado within the warranty period. Returns
must be preauthorized by contact with DEI's customer service department.
Written documentation of such preauthorization shall be included with the
returned item.
At DEI's discretion, DEI may elect to repair or replace the equipment claimed
to be defective or refund the original purchase price, plus taxes and
transportation charges incurred by the purchaser.
This Warranty shall not apply to any product that has been:
1. Repaired, worked on, or altered by persons unauthorized by DEI;
2. Subjected to misuse, neglect, or damage by others; or
3. Connected, installed, adjusted, or used in a manner not authorized in the
instructions or specifications furnished by DEI.
This warranty is the purchaser's sole remedy for claimed defects in the
equipment sold or manufactured by DEI. DEI's liability to the purchaser is
limited to the repair or replacement of the claimed defective equipment or, at
DEI's option, refund of the purchase price, taxes and transportation charges
incurred by the purchaser. DEI will not be responsible for or liable to the
purchaser for consequential losses or damages asserted to be attributable to
a claimed defect in the equipment provided.

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Changes made by DEI in the design or manufacture of similar equipment
which are effected subsequent to the date of shipment of the warranted
equipment to the purchaser are reflective of DEI's program of constant
product development and improvement and shall not be construed as an
acknowledgement of deficiency in the product shipped to purchaser. DEI will
be under no obligation to make any changes to product previously shipped.