BNC PVX-4150 User manual

BNC PVX-4150
BERKELEY NUCLEONICS CORPORATION
PVX-4150 PULSE GENERATOR
OPERATION MANUAL
Berkeley Nucleonics Corp.
San Rafael USA
415-453-9955

BNC PVX–4150
Manual Ver. 2
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TABLE OF CONTENTS
1.0 GENERAL DESCRIPTION ..........................................................................4
2.0 SPECIFICATIONS.......................................................................................5
3.0 SAFETY.......................................................................................................6
3.1 Operating Safety Summary...............................................................6
3.1.1 Power Source......................................................................6
3.1.2 Grounding............................................................................7
3.1.3 Cover Removal....................................................................7
3.1.4 General Operating Precautions...........................................7
3.2 Servicing Safety Summary................................................................7
3.2.1 Servicing Procedure............................................................7
3.2.2 Internal Energy Storage.......................................................7
4.0 OPERATING CONSIDERATIONS...............................................................9
4.1 Output Cabling..................................................................................9
4.2 Load Simulation ................................................................................9
4.3 Trigger Input......................................................................................9
4.4 Pulse Voltages +V IN and -V IN........................................................9
4.5 Output Pulse Considerations.............................................................9
4.6 Controls and Indicators .....................................................................10
4.6.1 Power Switch and LED........................................................10
4.6.2 Enable Switch and LED.......................................................10
4.6.3 Gate Connector...................................................................11
4.6.4 Gated LED...........................................................................11
4.6.5 Over Current LED................................................................11
4.6.6 Control Error LED................................................................11
4.6.7 Current Monitor....................................................................11
4.6.8 Voltage Monitor ...................................................................11
4.7 Remote Control.................................................................................12
5.0 PREPARATION FOR USE ..........................................................................14
5.1 General .............................................................................................14
5.2 Initial Inspection ................................................................................14
5.3 Electrical Installation..........................................................................14
5.3.1 Input Power Cord.................................................................14
5.4 Electrical Check ................................................................................14
5.4.1 Power-Up ............................................................................14
6.0 OPERATING INSTRUCTIONS....................................................................16
6.1 Power-Up Procedures.......................................................................16
6.2 Power-Down Procedures ..................................................................16
7.0 TROUBLESHOOTING.................................................................................17
7.1 Troubleshooting Procedures.............................................................17
7.1.1 Fuses...................................................................................18
7.2 Factory Service.................................................................................18
8.0 SYSTEM FAILURE MODES........................................................................19

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8.1 Over-Current Failure .........................................................................19
9.0 WARRANTY ................................................................................................19
APPENDIX.........................................................................................................21
Typical Output Waveforms......................................................................21

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********** WARNING **********
SAFE OPERATING PROCEDURES AND PROPER
USE OF THE EQUIPMENT ARE THE
RESPONSIBILITY OF THE USER OF THIS
SYSTEM.
Berkeley Nucleonics Corporation (BNC) 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 BNC PVX-4150 pulse generator is a high voltage solid state pulser
designed to drive capacitive loads such as grids, deflection, reflection and
acceleration plates.
The PVX-4150 will generate an output voltage swing of 1500 volts, and output
current of 16 amperes peak and .05 amperes continuous. It produces very flat
voltage pulses to DC into a capacitive load.
The PVX-4150 Pulser can generate single-ended output pulses from ground
to +1500V or from ground to -1500V, and can also generate pulses
originating from a voltage offset from ground. This offset can be from -1500V
to +1500V, with a maximum power supply voltage differential (Vhigh - Vlow)
≤1500V.

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2.0 SPECIFICATIONS
All specifications are measured into a 50pF load connected with 6 feet (~1.8M) of RG-62 (93Ω) coaxial cable
INPUT DC VOLTAGE +V IN (Vhigh)
Source External
Absolute Maximum Value +1500 volts
Relative Maximum Value +1500 volts above -V IN level
Absolute Minimum Value -1500 volts
Relative Minimum Value 0 volts above –V IN level
Input Connector Type SHV, Rear Panel (+V IN)
INPUT DC VOLTAGE -V IN(Vlow)
Source External
Absolute Maximum Value +1500 volts
Absolute Minimum Value -1500 volts
Input Connector Type SHV, Rear Panel (-V IN)
OUTPUT PULSE VOLTAGE
Maximum Value ±1500 volts (-V IN - +V IN)
Minimum Value 0 volts
Means of Adjustment Controlled By Power Supply Input
Voltages
Output Connector Type SHV, Rear Panel (OUTPUT)
GATE
Gate Source External
Gate Input +5V ±1V into 50Ω
Gate Rise Time <20ns
Gate Input Connector Type BNC, Front Panel
VOLTAGE MONITOR
Voltage Monitor 1000:1 into 1 MegΩ, 20 MHz Bandwidth
Limit
Voltage Monitor Connector Type BNC, Front Panel
CURRENT MONITOR
Current Monitor Type 10A/V into 50Ω, 20 MHz Bandwidth
Limit
Current Monitor Connector Type BNC, Front Panel

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OUTPUT PULSE ELECTRICAL CHARACTERISTICS
Pulse Rise Time <25ns 1500V (10%-90%, 50pF load)
Pulse Fall Time <25ns (10%-90%)
Pulse Width <60ns to DC, controlled by input gate
Pulse Recurrence Frequency Single Shot to 240KHz, controlled by
input gate (1)
Droop <1% into a capacitive load
Maximum Duty Cycle Continuous
Maximum Power Dissipation Into A
Capacitive Load (CV2F) 150 Watts, Derated at 2W/°C over 25°C
ambient (1)
GENERAL
Support Power 90VAC to 240VAC, 50/60Hz
Dimensions (Excluding Connectors) 19” W x 5.2” H x 13” D (48.25cm W x
13.2cm H x 33cm D)
Weight (Approximate) 18 lbs. (8.2 Kilograms)
These specifications are measured driving a 50pF load connected with 6 feet of RG-62 cable, at 1500V output.
However the PVX-4150 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 1500V, the PVX-
4150 can operate at continuous pulse recurrence frequencies above 240KHz. The PVX-4150 can also drive resistive
or inductive loads, within limitations. Contact BNC for additional information and applications assistance.
(1) The power dissipated in the PVX-4150 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-4150, 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-4150 is 200pF, and RG-62 cable is 13pf/foot.) Given the
maximum dissipation of 150W, the maximum load capacitance, frequency and/or voltage at which the PVX-4150 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.
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-4150.
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-4150 is designed to operate from a power source that will not apply
more than 240 volts between the supply conductors or between either supply
conductor and ground.

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A protective grounding connection by way of the grounding conductor in the
AC power cord is essential.
3.1.2 Grounding
The PVX-4150 is grounded through the grounding conductor of the AC power
cord. To avoid electrical shock, plug the PVX-4150 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-
4150 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-4150 is not safety interlocked. Extreme caution
should be exercised when removing the cover.
Any pulsed power system is capable of random triggering via transients.
Therefore when the PVX-4150 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-4150 contains dangerous voltages and stored energy. BNC
strongly recommends that all repairs and adjustments be performed by
factory qualified personnel. BNC 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-4150 contains capacitors that are used as energy storage elements.
When charged, these capacitors contain approximately 0.5 joules of stored
energy. This is sufficient energy to cause serious injury. Assure that the AC

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power cord is disconnected from the driver, and that the capacitor bank
is fully discharged and a shorting strap installed before any repairs or
adjustments are attempted. 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 3000VDC and 220VAC or greater. Dangerous
voltages, floating ground planes and energy storage exist at several locations
in the PVX-4150. Touching connections and/or components could result in
serious injury.

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4.0 OPERATING CONSIDERATIONS
4.1 Output Cabling
The PVX-4150 is designed to drive capacitive loads with fast rise times. Since
the current out of the PVX-4150 is limited, the lower the capacitance, the
faster the risetime. Given fixed load characteristics, only the interconnecting
cable type and length will vary the output capacitance.
The unit is supplied with a 6 foot length of RG-62 coaxial cable which has a
capacitance of 13.5pF per foot. The unit is series terminated in the
characteristic impedance of this cable, which is 93Ω. BNC recommends that
the shortest length of cable possible be used to ensure the fastest possible
rise times and best pulse fidelity.
4.2 Load Simulation
This unit was tested with a 50pF capacitive load connected to the output with
6 feet of RG-62 coaxial cable.
4.3 Trigger Input
An input trigger of +5V ±1V into 50Ωwith a risetime of <20ns is required to
gate on the PVX-4150. 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-4150 trigger input. The input trigger
amplitude should be set using a 50Ωload (e.g. a 50Ωscope input) before
connecting it to the PVX-4150. 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-4150 Pulser is rated at a maximum pulse output voltage of
±1500VDC. Proper precautions should be taken by the user to ensure that
the maximum voltage is not exceeded.
4.5 Output Pulse Considerations
The PVX-4150 Pulser can generate single-ended output pulses from ground
to +1500V or from ground to -1500V, and can also generate pulses
originating from a voltage offset from ground. This offset can be from -1500V
to +1500V, but the maximum power supply voltage differential (Vhigh - Vlow)
should never exceed 1500V. The Vhigh supply should always be equal to or
greater than the Vlow supply, but never greater than 1500V above the Vlow

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supply. Therefore the Vlow supply may be set to any voltage between -1500V
and +1500V, and the Vhigh supply may be set to any voltage between -
1500V and +1500V, but the voltage difference between Vlow and Vhigh
should never exceed +1500V. 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-4150 can 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).
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 Enable Switch and LED
The enable 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.
If the enable LED is not illuminated, the PVX-4150 will not generate an
output pulse. The external interlock circuit (on the rear panel DSUB
Input Gate:
+5V
Ground
Output Pulse:
V
high
V
low
Generating a Negative Pulse With The PVX-4150

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connector) must be satisfied before the PVX-4150 can be enabled. If the
Enable LED does not illuminate when the enable switch is pressed,
confirm that the external interlock circuit is satisfied.
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-4150 will not generate an output
pulse.
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 ~250KHz. 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.
4.6.8 Voltage Monitor
The BNC connector labeled "V MON" provides a 1V/1000V monitor of the
output pulse. This monitor should be terminated into 1 MegΩ, such as the
1 MegΩinput of an oscilloscope. Please note that due to the 20MHz
Bandwidth limit on the V-MON, the rise and fall times will not be accurate.

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4.7 Remote Control
The PVX-4150 has the capability to be operated through remote controls.
The following table provides the pinout of the 15 pin DSUB connector on
the rear panel.
PIN FUNCTION DESCRIPTION
1 GND Ground
2 GND Ground
3 GND Ground
4 GND Ground
5 GND Ground
6
Enable Status
Output: Active low, open drain, 24 mA
maximum ON, 24 V DC maximum OFF
7
Control Error Status
Output: Active low, open drain, 24 mA
maximum ON, 24 V DC maximum OFF (not
used)
8
Power Status
Output: Active low, open drain, 24 mA
maximum ON, 24 V DC maximum OFF
9 Enable Input: Low-to-high transition to enable, disable,
reset
10 Invert Input: Pull low to invert the Gate input
11 Remote Input: Pull low for remote operation
12 Interlock Input: Pull low to satisfy the interlock
13 Auto Reset Input: Pull low to enable auto reset
14
Over Current Status
Output: Active low, open drain, 24 mA
maximum ON, 24 V DC maximum OFF
15
Gated Status
Output: Active low, open drain, 24 mA
maximum ON, 24 V DC maximum OFF

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not want to operate in the remote mode, pins 4 and 12 and pins 5 and 13
should be jumpered together. This satisfies the interlock and enables the
autoreset function.
The PVX-4150 is shipped with a mating DSUB connector installed, and
with pins 4 and 12 and pins 5 and 13 jumpered. Therefore as shipped,
remote operation is disabled. This connector must be installed in order
to satisfy the interlock circuit. If it is not installed, the unit cannot be
enabled.
The control pins on the remote connector are internally pulled high. For
remote operation, the REMOTE pin should be pulled low. This disables
the Front Panel ENABLE switch to prevent local operation. The remote
ENABLE, INTERLOCK, INVERT, and AUTO RESET inputs are always
active, regardless of the state of this REMOTE signal. If the ENABLE
signal is momentarily pulled low, the unit will be enabled, or a fault will be
cleared, on the rising edge of that signal. If the INVERT pin is pulled low,
the gate pulses going in to the unit will become inverted internally.
Therefore, the output pulse will be inverted from that of the input gate.
The INTERLOCK pin must be pulled low or jumpered to pin 4 in order
to satisfy the PVX-4150’s interlock circuit. If the INTERLOCK pin is
not pulled low or jumpered to pin 4, the user will not be able to
enable the output. If the user is using the INTERLOCK pin, it should be
pulled low to satisfy the interlock. Otherwise, it should be jumpered to pin
4.
The AUTORESET function allows the user to choose how to clear the
faults. If the AUTORESET pin is pulled low, the unit will reset itself after
6msec when a fault occurs such as an overcurrent or interlock fault. If the
AUTORESET is not pulled low, the user will have to reset faults manually.
To reset a fault, the ENABLE pin should be pulled low two times: Once to
reset the fault, and the second time to enable the output. If the user does

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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.
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.
5.3 Electrical Installation
Standard units are shipped ready for use with a nominal 100 to 240 VAC
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. Install the mating rear panel DSUB connector supplied with the unit. This
connector has pins 4 and 12 and pins 5 and 13 jumpered. Therefore as
shipped, remote operation is disabled. This connector must be installed
in order to satisfy the interlock circuit. If it is not installed, the unit
cannot be enabled. In order to operate the PVX-4150 remotely or to use
an external interlock, wire the DSUB connector accordingly (see the
“Remote Control” section above).

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2. Before connecting the pulse generator to the PVX-4150, 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.
3. Connect the positive output power supply to the rear panel SHV connector
labeled +V IN. Connect the negative output power supply to the rear panel
SHV connector labeled -V IN. For +1500V 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-4150 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-
4150 labeled "GATE".
5. The PVX-4150 is powered up in a faulted condition. Once the Gate is
connected, the fault should be cleared within 5 seconds.
6. Enable the pulses by pressing the “ENABLE” button. The green LED
labeled “OUTPUT ENABLED” should light. Note that if the above
mentioned fault is not clear, the output will not be enabled until the 5
second time limit has expired and the “ENABLE” button in pressed again.
7. Connect an appropriate load to the rear panel SHV output connector.
8. It is possible to monitor the output voltage in two ways. One way is by
connecting an appropriate high voltage probe to the output load, utilizing
an appropriate attenuator if necessary. The second and easier way is to
attach a 50 Ohm coax to the V-MON connector on the front panel. Please
note that due to the 20MHz Bandwidth limit on the V-MON, the rise and
fall times will not be accurate.
9. Slowly turn up the high voltage power supplies. The PVX-4150 should
produce an output pulse, with a pulse width and pulse recurrence
frequency following that of the incoming trigger.
10.If there is no output from the PVX-4150, or the output is severely distorted,
turn OFF the high voltage power supplies. Leave the PVX-4150 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.

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6.0 OPERATING INSTRUCTIONS
This section provides basic operating instructions for the PVX-4150.
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-4150 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.
Never short-circuit the pulse voltage output of the pulser. Failure to
observe these precautions can result in potential electric shock to
personnel, arcing, and damage to the connectors and system.
3. The covers of the PVX-4150 are not safety interlocked. Extreme caution
should be exercised when removing the covers.
4. Pulsed power systems are capable of random triggering via transients and
therefore when the PVX-4150 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. Monitor the output of the PVX-4150 on an oscilloscope utilizing a high
voltage probe connected to the output load, or with a coax attached to the
V-MON in the front panel. Set the output amplitude of the PVX-4150 to
the desired level by adjusting the output voltage of the high voltage power
supplies.
4. 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-4150. The output pulse voltage will
follow the input trigger, but will not replicate in time the exact duration of
the input trigger due to the system propagation delay.
6.2 Power-Down Procedures
1. Set the controls of the high voltage power supplies to zero.
2. Turn off the high voltage power supplies.

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3. Leave the PVX-4150 connected to the AC input without high voltage and
with all connectors in place for approximately five minutes to bleed off the
stored energy.
4. Disconnect the AC power to the unit.
7.0 TROUBLESHOOTING
WARNING
The PVX-4150 contains capacitors that are used as energy storage elements.
When charged, these capacitors contain approximately 0.5 joules of stored
energy. This is sufficient energy to cause serious injury. Assure that the AC
power cord is disconnected from the driver, and that the capacitor bank
is fully discharged and a shorting strap installed before any repairs or
adjustments are attempted. 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 3000VDC and 220VAC or greater. Dangerous
voltages, floating ground planes and energy storage exist at several locations
in the PVX-4150. Touching connections or components could result in serious
injury.
7.1 Troubleshooting Procedures
Before attempting to service or troubleshoot the PVX-4150, review the
servicing safety summary in Section 3.0.
The power MOSFETs utilized in the PVX-4150 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, BNC customer service can
be contacted for further assistance.

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SYMPTOM SOLUTIONS
"POWER" LED Does
Not Illuminate
Cannot Enable Output
No Output Pulse
•AC power not plugged in.
•Fuse(s) are blown. See fuse replacement
instructions in Section 7.1.1
•External remote interlock circuit is not
satisfied
•Output is not enabled
•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 BNC customer
service.
7.1.1 Fuses
To avoid fire hazard or damage to the driver, use only the fuse types listed
below. Fuse replacement should be performed by qualified personnel only.
Assure that the AC power cord is disconnected from the driver, and that
the capacitor bank is fully discharged and a shorting strap installed
before fuse replacement is attempted. 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 3000VDC and 220VAC or
greater.
FUSE LOCATION FUSE VALUE
AC Entry Module 3A, 250VAC Fast Blow
7.2 Factory Service
If the procedures above fail to resolve an operational problem, please contact
the factory for further assistance:
Berkeley Nucleonics Corp. San Rafael USA
Call: [phone]
Email: [e-mail]

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8.0 SYSTEM FAILURE MODES
The PVX-4150 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-4150. FAILURE TO DO SO
VOIDS THE WARRANTY.
8.1 Over-Current Failure
When the output is shorted, the PVX-4150 can deliver in excess of 16A of
current (depending on cabling, pulse power supply setting, etc.). A current
pulse of this magnitude is in excess of the driver's specifications. 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 Berkeley Nucleonics Corp. (BNC) except as
follows:
BNC 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. BNC will repair or
replace, at BNC'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 BNC's factory in Colorado within the warranty period. Returns must be
preauthorized by contact with BNC's customer service department. Written
documentation of such preauthorization shall be included with the returned
item.
At BNC's discretion, BNC 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 BNC;
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 BNC.