Spellman ST SERIES, STA SERIES, STR SERIES Instruction Manual

R

Instruction Manual

ST/STA/STR SERIES

MODEL :
SERIAL# :
DATE :

SPELLMAN
HIGH VOLTAGE ELECTRONICS
CORPORATION

475 Wireless Blvd.
Hauppauge, New York, 11788

[phone]*FAX: [phone]*
E-mail: [e-mail]
Website: www.spellmanhv.com

High Voltage Power Supply

ST/STA/STR SERIES MANUAL 118108-001 Rev C

IMPORTANT SAFETY PRECAUTIONS

SAFETY

THIS POWER SUPPLY GENERATES VOLTAGES THAT ARE DANGEROUS AND MAY BE FATAL.

OBSERVE EXTREME CAUTION WHEN WORKING WITH THIS EQUIPMENT.

High voltage power supplies must always be grounded.

Do not touch connections unless the equipment is off and the

Capacitance of both the load and power supply is discharged.

Allow five minutes for discharge of internal capacitance of the power supply.

Do not ground yourself or work under wet or damp conditions.

SERVICING SAFETY

.

Maintenance may require removing the instrument cover with the power on.

Servicing should be done by qualified personnel aware of the electrical hazards.

WARNING note in the text call attention to hazards in operation of these units

that could lead to possible injury or death.

CAUTION notes in the text indicate procedures to be followed to avoid possible

damage to equipment.

Copyright © 2000, Spellman High Voltage Electronics Corporation. All Rights Reserved.

This information contained in this publication is derived in part from proprietary and patent data. This information has

been prepared for the express purpose of assisting operating and maintenance personnel in the efficient use of the

model described herein, and publication of this information does not convey any right to reproduce it or to use it for

any purpose other than in connection with installation, operation, and maintenance of the equipment described.

118004-001 REV. B

WICHTIGE SICHERHEITSHINWEISE

SICHERHEIT

DIESES HOCHSPANNUNGSNETZTEIL ERZEUGT LEBENSGEFÄHRLICHE HOCHSPANNUNG.

SEIN SIE SEHR VORSICHTIG BEI DER ARBEIT MIT DIESEM GERÄT.

Das Hochspannungsnetzteil muß immer geerdet sein.

Berühren Sie die Stecker des Netzteiles nur, wenn das Gerät ausgeschaltet ist und die elektrischen

Kapazitäten des Netzteiles und der angeschlossenen Last entladen sind.

Die internen Kapazitäten des Hochspannungsnetzteiles benötigen ca. 5 Minuten, um sich zu entladen.

Erden Sie sich nicht, und arbeiten Sie nicht in feuchter oder nasser Umgebung.

SERVICESICHERHEIT

Notwendige Reparaturen können es erforderlich machen, den Gehäusedeckel während des Betriebes zu

entfernen.

Reparaturen dürfen nur von qualifiziertem, eingewiesenem Personal ausgeführt werden.

“WARNING” im folgenden Text weist auf gefährliche Operationen hin, die zu Verletzungen oder zum Tod

führen können.

“CAUTION” im folgenden Text weist auf Prozeduren hin, die genauestens befolgt werden müssen, um

eventuelle Beschädigungen des Gerätes zu vermeiden.

118004-001 REV. B

PRECAUTIONS IMPORTANTES POUR VOTRE SECURITE

CONSIGNES DE SÉCURITÉ

CETTE ALIMENTATION GÉNÈRE DES TENSIONS QUI SONT DANGEUREUSES ET PEUVENT ÊTRE FATALES.

OYEZ EXTRÊMENT VIGILANTS LORSQUE VOUS UTILISEZ CET ÉQUIPEMENT.

S

Les alimentations haute tension doivent toujours être mises à la masse.

Ne touchez pas les connectiques sans que l’équipement soit éteint et que la capacité à la fois de la charge et de

l’alimentation soient déchargées.

Prévoyez 5 minutes pour la décharge de la capacité interne de l’alimentation.

Ne vous mettez pas à la masse, ou ne travaillez pas sous conditions mouillées ou humides.

CONSIGNES DE SÉCURITÉ EN CAS DE REPARATION

La maintenance peut nécessiter l’enlèvement du couvercle lorsque l’alimentation est encore allumée.

Les réparations doivent être effectuées par une personne qualifiée et connaissant les risques électriques.

Dans le manuel, les notes marquées « WARNING » attire l’attention sur les risques lors de la manipulation de ces

équipements, qui peuvent entrainer de possibles blessures voire la mort.

Dans le manuel, les notes marquées « CAUTION » indiquent les procédures qui doivent être suivies afin d’éviter

d’éventuels dommages sur l’équipement.

118004-001 REV. B

IMPORTANTI PRECAUZIONI DI SICUREZZA

SICUREZZA

QUESTO ALIMENTATORE GENERA TENSIONI CHE SONO PERICOLOSE E

POTREBBERO ESSERE MORTALI.

PONI ESTREMA CAUTELA QUANDO OPERI CON QUESO APPARECCHIO.

Gli alimentatori ad alta tensione devono sempre essere collegati ad un impianto di terra.

Non toccare le connessioni a meno che l’apparecchio sia stato spento e la capacità interna

del carico e dell’alimentatore stesso siano scariche.

Attendere cinque minuti per permettere la scarica della capacità interna dell’alimentatore

ad alta tensione.

Non mettere a terra il proprio corpo oppure operare in ambienti bagnati o saturi d’umidità.

SICUREZZA NELLA MANUTENZIONE.

Manutenzione potrebbe essere richiesta, rimuovendo la copertura con apparecchio

acceso.

La manutenzione deve essere svolta da personale qualificato, coscio dei rischi elettrici.

Attenzione alle AVVERTENZE contenute nel manuale, che richiamano all’attenzione ai

rischi quando si opera con tali unità e che potrebbero causare possibili ferite o morte.

Le note di CAUTELA contenute nel manuale, indicano le procedure da seguire per evitare

possibili danni all’apparecchio.

118004-001 REV. B

Table of Contents

1. INTRODUCTION

1.1 Description of the ST/STR/STA Series ...............................................................1

1.2 Standard Features .................................................................................................1

1.2.1 Remote Operating Features.....................................................................2

1.2.2 System Status and Fault Diagnostic Display ..........................................3

1.3 Options .................................................................................................................4

1.4 Interpreting the Model Number ...........................................................................4

2. INSPECTION & INSTALLATION

2.1 Initial Inspection ..................................................................................................5

2.2 Input Requirements ..............................................................................................5

2.3 Mechanical Installation ........................................................................................5

2.4 Airflow Requirements ..........................................................................................5

3. OPERATING INSTRUCTIONS

3.1 Operation..............................................................................................................7

3.2 Standard Features .................................................................................................8

3.3 Digital Interface (RS-232/Ethernet) .....................................................................9

3.4 Reversible Polarity (1-10kV Units Only) ............................................................9

3.5 Multiple Chassis Systems (Power > 12kWs) .......................................................9

PAGE

4. PRINCIPLES OF OPERATION

4.1 Line Rectifier and Filtering ..................................................................................17

4.2 Inverter .................................................................................................................18

4.3 High Voltage Transformer ...................................................................................18

4.4 High Voltage Assembly .......................................................................................18

4.5 System Control PWB ...........................................................................................18

4.6 Front Panel Assembly ..........................................................................................18

4.7 Rear Panel Interface PWB ...................................................................................18

5. OPTIONS

5.1 Blank Front Panel ................................................................................................19

5.2 High Stability .......................................................................................................19

5.3 High Voltage Cable Length .................................................................................19

5.4 400VAC ...............................................................................................................19

5.5 180-264Vac Single Phase Input (1PH) ................................................................19

5.6 Custom Designed Models ....................................................................................19

5.7 Parallel Option Units............................................................................................20

6. MAINTENANCE

6.1 Periodic Servicing ................................................................................................22

ST/STR/STA MANUAL i 118107-001 REV J

6.2 Performance Test .................................................................................................22

6.3 High Voltage Dividers .........................................................................................22

7. REPLACEMENT PARTS

7.1 Replacement Parts ................................................................................................23

7.2 Correspondence and Ordering Spare Parts ..........................................................23

8. FACTORY SERVICE

8.1 Warranty Repairs .................................................................................................23

8.2 Factory Service Procedures ..................................................................................23

8.3 Ordering Options and Modifications ...................................................................23

8.4 Shipping Instructions ...........................................................................................23

APPENDIX

A. RS-232 and Ethernet Digital Interface Information
B. TI Upload Procedure (Firmware Update Procedure)
C. Standard ST GUI Information
D. Specification Control Drawing (Custom Models Only)

LIST OF FIGURES / TABLES

Figure 3.1 Typical Operating Setup ...............................................................................9

Figure 3.2A Remote Programming via Voltage Source ....................................................10

Figure 3.2B Remote Programming via External Resistance..............................................10

Figure 3.3 Remote Monitor Test Point Designations ......................................................11

Figure 3.4 Remote Control Power On, HIGH VOLTAGE ON and HV OFF ................11

Figure 3.5 External Inhibit Interface Circuit ...................................................................12

Figure 3.6 External Interlock Interface Circuit ...............................................................12

Figure 3.7 Remote HIGH VOLTAGE ON and HIGH VOLTAGE OFF .......................13

Figure 3.8 Remote Overvoltage Adjust Interface ...........................................................13

Figure 3.9 Remote Status and Fault Indicator Interface ..................................................14

Figure 3.10 Rear Panel Interface Connecter .....................................................................15

Figure 4.1 List of Main Assemblies ................................................................................16

Table 1 Input Requirements ........................................................................................6

ST/STR/STA MANUAL ii 118107-001 REV J

Chapter 1

T

INTRODUCTION

1.1 Description of the
ST/STR/STA Series

ST/STR

STA

he ST series of high voltage power supplies provides
very well regulated, low ripple high voltage in a

highly efficient, compact design. Extremely stable
voltage and current outputs result in significant
performance improvements over previously available
technology.
All of these advancements are possible only by
Spellman’s long history in high voltage power conversion
technology. This series of power supplies utilizes
extremely advanced quasi-resonant PWM conversion
techniques, along with sophisticated digital technology.
The output voltage, current and power are continuously
adjustable over their full rated range. The standard ST
operates from 180-264Vac, three phase power and is
forced air cooled. An optional 360-528Vac input
(400VAC) is available. Custom units to meet special
requirements and specific applications can also be
provided.

The STR Series high voltage power supplies are identical
in form, fit and function to the ST Series the following
exceptions:

1) The STR only provides 6kW’s of output power.

2) The ripple specification for the STR is 0.1% p-p

+1Vrms.

3) It is not possible to parallel STR chassis. If

additional power is required use an ST Series
unit.

4) The SRT is available with an optional 180-

264Vac single phase input voltage.

Aside from these four points, the STR and ST are for all
practical purposes identical. For the sake of clarification
the following text only references ST, but all points apply
to the STR Series as well.

The STA Series of high voltage power supplies are
identical to the ST Series with the following exceptions:

1) The STA is a 5.25 inch tall (3U) chassis.

2) The STR only provides 4kW’s of output power.

3) The ripple specification for the STA is 0.1% p-p

+1Vrms.

4) It is not possible to parallel STA/STR chassis. If

additional power is required use an ST Series
unit.

5) The STA is available with an optional 180-

264Vac single phase input voltage.

Customary warranty terms apply to standard units.
Consult the Spellman Sales Department about the
warranty for custom/X numbered units.

1.2 Standard Features

The ST series incorporates several standard features and
software configurable items designed to optimize user
utility, satisfaction and safety.

FRONT PANEL CONTROL POWER/HIGH
VOLTAGE ON/ HIGH VOLTAGE OFF SWITCHES:

These intuitive front panel controls allow the user to

ST/STR/STA MANUAL 1 118107-001 REV J

easily turn the unit on and enable/disable the generation
of high voltage.

FRONT PANEL INDICATOR LAMPS: CONTROL
POWER ON, HIGH VOLTAGE OFF and HIGH
VOLTAGE ON indicators are integral with the control
switches and equipped with dual lamps for redundancy
and safety.

displaying an “ARC” Fault (Arc Trip). See Chapter 3 for
operating details and information for user customization
for these parameters via the software and the digital
interface.

INTERNAL FAULT PROTECTION: The ST series
continually monitors internal circuits critical to the proper
operation of the power supply. In the event that one of
these circuits malfunctions, the fault detection circuit
turns off the high voltage and reverts the unit to the
POWER DOWN mode with the CONTROL POWER ON
indicator lamp flashing ON/OFF slowly. The applicable
fault indicator will be illuminated on the front panel
requiring the user to clear (cycle the CONTROL POWER
ON switch, cycle the AC line power or toggle the
Reset/External Inhibit signal line).

FRONT PANEL POTENTIOMETERS: Ten turn
locking counting dials are provided for easy programming
of the desired voltage and current regulation values.

FRONT PANEL DIGITAL METERS: 3.5 digit meters
are provided to view the output voltage and current. A
convenient Preset View Feature is provided: If the HIGH
VOLTAGE OFF button is depressed and held in, the
present voltage and current programming values will be
displayed in actual kV and mA on the front panel meters.

ETHERNET AND RS-232 INTERFACE: DSP based
SMT circuitry provides both Ethernet and RS-232 digital
interfacing capability simplifying the integration of the
ST into your system design. A VB GUI is provided for
the RS-232, the Ethernet has an imbedded applet for
control.

SLOW START RAMP TIME: This feature provides a
gradual increase of high voltage until the preset operating
point is reached. The slow start time is factory set for ten
seconds. Other slow start times can be software
configured using the digital interface.

ARC QUENCH/ARC RERAMP/ARC TRIP: These
features allow the user to tailor the power supply to meet
specific needs in dynamic load applications. The standard
configuration is if an arc occurs, the output is inhibited for
approximately 200mS (Arc Quench), and then the output
is ramped up to the preset level with the Slow Start
circuitry time constant (Arc ReRamp). If four arcs occur
in a ten second time period the unit will shut down

OUTPUT CABLE: All standard models are provided
with a ten foot shielded high voltage output cable. The
cable is designed so that it can be easily removed from the
mating receptacle located on the rear of the chassis.

1.2.1 Remote Operating Features

REMOTE PROGRAMMING: Allows remote
adjustment of the output voltage, current, power and
overvoltage regulation parameters via the use of external
voltage sources.

REMOTE MONITOR: Allows remote monitoring of
the output voltage, current and power test points.

REMOTE HIGH VOLTAGE CONTROL: Allows
remote control of the HIGH VOLTAGE ON and HIGH
VOLTAGE OFF functions. Signals are also provided for
remote indication of HIGH VOLTAGE ON and HIGH
VOLTAGE OFF status.

REMOTE POWER ON: Allows remote control of
CONTROL POWER ON/OFF function. This feature also
allows remote reset of the power supply in case of
SYSTEM FAULT shutdown.

RESET/EXTERNAL INHIBIT: This circuit will reset
any latched power supply faults and inhibit the high
voltage output. A logic low/ground, will reset any fault(s)
while inhibiting the high voltage output. A logic
high/open will restore the high voltage output to the
preset level. NOTE: The External Inhibit circuit should
NOT be used for protection against injury or for safety
interlocking. See External Interlock for this type of safety
control.

EXTERNAL INTERLOCK: Interlock connections are
provided on the rear panel interface connecter for
connection to a safety switch. The unit will not operate
unless the interlock circuit is closed. During high voltage
operation, opening the interlock circuit will cause the

ST/STR/STA MANUAL 2 118107-001 REV J

High Voltage to shut off. This circuit should be used for
safety interlock circuits. Spellman strongly recommends
the use of External Interlocking for safety purposes.

1.2.2 System Status and Fault

Diagnostic Display

“Dead Front” backlight type indicators provide system
operation and fault condition information. If a fault occurs
the power supply will revert to the POWER DOWN
mode. This is indicated by the flashing of the CONTROL
POWER ON indicator. To reset the latched fault: cycle
the CONTROL POWER ON switch, cycle the AC line
power or toggle the Reset/External Inhibit signal line.

VOLTAGE CONTROL: Indicates the output voltage
regulator circuit is maintaining voltage regulation.

CURRENT CONTROL: Indicates the output current
regulator circuit is maintaining current regulation.

voltage by the user via the remote overvoltage
programming capability, see Chapter 3 for more details.

OVER CURRENT: Indicates the output current has
exceeded the programmed current trip level when the
AOL (Adjustable Overload Trip) feature has been
software configured using the digital interface.

OVER POWER: Indicates the output power has
exceeded the programmed regulating level. This signal
could be either the internal potentiometer or the user
provided remote power programming signal, dependent
on configuration.

OVER TEMP: Indicates that excessive temperature has
been sensed within the chassis and internal protection
circuitry has shut down the power supply.

ARC: Indicates that an arc has occurred (one second
flash) or that the ARC Intervention Circuitry has
shutdown the power supply due to excessive arcing
(latched “ARC” fault).

AC FAULT: Indicates a problem with the front end AC
input circuitry and the corresponding generated inverter
buss voltages.

RGLT ERR: Indicates a failure in the voltage, current or
power regulation circuitry. This fault usually occurs
when there is a lack of output power to maintain proper
regulation. Possible causes could be due to low AC input
voltage (below low line parameters, or a missing phase)
or a malfunction of the power supply preventing it from
generating the voltage/current being requested.

POWER CONTROL: Indicates the output power
regulator circuit is maintaining power regulation.

HV INHIBIT: Indicates the high voltage supply is being
inhibited by either the EXTERNAL INHIBIT signal line
or by internal protection circuitry.

INTLK CLOSED: Indicates the EXTERNAL
INTERLOCK connections are in the closed position.

INTLK OPEN: Indicates the EXTERNAL
INTERLOCK connections are in the open position. This
also indicates opening of internal power supply interlocks.
It is not possible to enable HIGH VOLTAGE with an
open EXTERNAL INTERLOCK.

SYSTEM FAULT: Indicates an internal fault or parallel
chassis fault (in multiple chassis systems) has occurred.

OVER VOLTAGE: Indicates the overvoltage protection
circuitry has caused the power supply to turn off. The
default setting for the overvoltage protection circuitry is
internally set to 105% of rated output voltage. This level
can be set to anywhere from 0- 105% of rated output

ST/STR/STA MANUAL 3 118107-001 REV J

1.3 Options

BFP Blank Front Panel

Local control functionality and metering is removed from
the standard front panel, a popular cost saving measure
for OEM applications where the unit will only be
controlled remotely.

HS High Stability

The standard voltage feedback divider is replaced with a
high precision voltage feedback divider providing a
50ppm/°C temperature coefficient specification.

LL(X) High Voltage Cable Length

Custom length high voltage output cables, indicated in
foot measurement units. Various predetermined lengths
are available along with entirely custom lengths; contact
Spellman Sales Department for details.

400VAC 360-528Vac Input

This option factory configures the ST/STR to operate
from 360-528Vac, three phase, 50/60Hz input power.
This option cannot be implemented in the field.

1.4 Interpreting the Model
Number:

The model number of the power supply describes its
capabilities. After the series name “ST” is:

● The maximum voltage in kV

● The polarity of the unit: positive (P) or negative (N). 1-

10kV units are inherently reversible by design requiring
and internal wiring change to swap polarity. All units
required a polarity selection to be made at time of order.

● The maximum output power in kilowatts

● The option codes for all options that are included.

● Custom units have a unique 4 digit X number after the

option code(s). This X number references a unique
specification control drawing that takes precedent over
the standard ST data sheet specifications.

1PH Single Phase Input

Optional 180-264Vac single phase input voltage,
available only on STR and STA.

See Section 5 for more information on these options.
With few exceptions, these options can be retrofitted to
your power supply at the factory in a short time. For price
and retrofit arrangements, contact Spellman’s Sales
Department at:

[e-mail]

ST/STR/STA MANUAL 4 118107-001 REV J

Chapter 2

I

Figure 2.1 ST/STR/STA

Airflow

Inspection and Installation

nitial inspection and preliminary checkout procedures
are recommended. For safe operation, please follow
the step-by-step procedures described in Chapter 3,

Operating Instructions.

2.1 Initial Inspection

Inspect the package exterior for evidence of damage due
to handling in transit. Notify the carrier and Spellman
immediately if damage is evident. Do not destroy or
discard any of the packing material used in a damaged
shipment.

After unpacking, inspect the panel and chassis for visible
damage.

Standard Spellman ST high voltage power supplies are
covered by a warranty. Custom and special order models
(with an X suffix in the model number) are also covered
by a warranty. Check the specific warranty terms by
referring to the Warranty document contained in this
operator’s manual.

2.2 Input Requirements

Units ordered with the 400VAC Option (360-528Vac)
do NOT have a rear panel circuit breaker. For proper
protection of the ST power supply a circuit breaker
protected, dedicated three phase electrical service must
be provided for each ST chassis. ST units are not phase
dependent; the three AC input phase connections can be
orientated in any manner with no adverse effect on
power supply performance. SEE TABLE 1

suitable for bench or tabletop operation. It is
strongly recommended to support the chassis by
guides or shelves.

2.4 Airflow Requirements

ST units are forced air cooled, air enters the
chassis via openings on the right and left side
panels and air is forcibly exhausted out the rear
panel via three fans. Whatever mechanical
installation is implemented airflow into and out
of the unit must not be compromised.
Additionally it is the responsibility of the user to
assure that air entering the unit is not above the
maximum ambient temperature of 40°C.
Airflow volume is 300cfm for ST units, 200 cfm
for STR units and 100 cfm for STA units.

2.3 Mechanical Installation

Units in the ST series have front panel holes for standard
EIA rack mounting. The rack must allow rear access for
cable connections. Units are fully enclosed and are

ST/STR/STA MANUAL 5 118107-001 REV J

UNIT/INPUT VOLTAGE

FACTORY CONFIGURATION

MAXIMUM INPUT CURRENT PER PHASE

ST 180-264Vac, 3 phase

Standard

50 amps

ST 360-528Vac, 3 phase

Optional (400Vac)

25 amps

STR 180-264Vac, 3 phase

Standard

25 amps

STR 360-528Vac, 3 phase

Optional (400Vac)

12.5 amps

STR 180-264Vac, 1 phase

Optional (1PH)

57 amps

STA 180-264Vac, 3 phase

Standard

17 amps

STA 180-264Vac, 1 phase

Optional (1PH)

38 amps

Table 1 Input Requirements

ST/STR/STA MANUAL 6 118107-001 REV J

Chapter 3
Operating Instructions

3.1 Operation

WARNING

THIS EQUIPMENT GENERATES

DANGEROUS VOLTAGES THAT MAY BE

FATAL. PROPER GROUNDING OF ALL

HIGH VOLTAGE EQUIPMENT IS ESSENTIAL.

WARNING

BEFORE CONNECTING THE POWER

SUPPLY TO THE AC LINE, FOLLOW THIS

STEP-BY-STEP PROCEDURE.

DO NOT CONNECT THE POWER SUPPLY

TO THE AC LINE UNTIL STEP ‘G’ IS

REACHED. FAILURE TO FOLLOW THESE

PROCEDURES MAY VOID THE WARRANTY.

A) Insure that the front panel CONTROL POWER
ON switch is in the OFF position (switch bezel out).

B) Check the input voltage rating on the nameplate
of the supply and make certain that this is the rating of the
available power source.

C) PROPER GROUNDING TECHNIQUE: The
chassis of high voltage power supply must be adequately

grounded, preferably to the local “system ground” (cold

water pipe ground, electrical conduit ground, copper
ground rod, etc) using a heavy gauge copper wire
securely connecting to the ¼-20 ground stud on the rear
panel of the of the unit. See Figure 3.1 for a typical
operating setup.

A heavy gauge user provided “load return” wire must be

connected from the low end of the load back to the ¼-20
ground stud on the rear panel of the power supply. Using
a separate external ground at the load is not
recommended.

A six foot long, captive, four-wire, unterminated line cord
is provided for connecting to the AC supply. The
BROWN, BLACK and BLUE wires are the three phase
inputs. The GREEN/YELLOW wire is for chassis safety
ground connection. This is a safety ground connection
and is NOT adequate for system grounding purposes.

Attach the output cable to the load.
D) Plug the high voltage output cable provided with

the unit into the rear of the supply and secure
appropriately.

E) Options Note: See section 5 for hook up and
operating instructions for the options on your unit.
Custom models may also require set up changes.

F) For initial turn-on, rotate the front panel
KILOVOLT control potentiometer fully counter­clockwise to the zero voltage position.

G) The input power cable may now be connected to
the AC power line.

H) Depress the CONTROL POWER ON switch.
The green light inside the switch should light up. The
unit is now in the HIGH VOLTAGE OFF mode. The
HIGH VOLTAGE OFF light should be lit.

I) Depress and hold the HIGH VOLTAGE OFF
switch. The front panel meters will now read the preset
value of the KILOVOLT control dial and the
MILLAMPERES control dial. To preset the desired level
of the current and voltage during operation, hold the
HIGH VOLTAGE OFF switch and rotate the appropriate
control dial while noting its corresponding meter reading.
Release the HIGH VOLTAGE OFF switch.

NOTE: No actual high voltage is being produced at this
time.

J) Depress the HIGH VOLTAGE ON switch. The
red light inside the switch should illuminate and the
output will slow start up to the preset level output voltage
and/or output current.

Note: The ST series is equipped with a slow start circuit
that ramps the output up to its maximum setting in
approximately 10 seconds after the HIGH VOLTAGE
ON switch is depressed.

K) To terminate the generation of output power,
depress the HIGH VOLTAGE OFF switch. In the HIGH
VOLTAGE OFF mode the power supply’s fault and
interface circuits are still active.

L) To turn off the power supply, depress the
CONTROL POWER ON switch to release the switch
bezel to the out position. All front panel lights should
extinguish.

ST/STR/STA MANUAL 7 118107-001 REV J

NOTE: If a power supply fault, or system monitoring
fault occurs, the power supply will revert to the POWER
DOWN mode. In this mode the output power will be
turned off. The CONTROL POWER ON lamp will flash
indicating a SYSTEM FAULT. To reset the SYSTEM
FAULT cycle the CONTROL POWER ON switch, cycle
the AC line power or toggle the RESET/EXTERNAL
INHIBIT signal line.

WARNING

AFTER TURNOFF, DO NOT HANDLE THE LOAD

UNTIL THE CAPACITANCE HAS BEEN

DISCHARGED! LOAD CAPACITANCE MAY BE

DISCHARGED BY SHORTING TO GROUND.

WARNING

THE VOLTMETER ON THE POWER SUPPLY

FRONT PANEL DOES NOT READ THE OUTPUT

VOLTAGE WHEN THE POWER IS TURNED OFF,

EVEN IF A CHARGE STILL EXISTS ON THE

LOAD.

CAUTION

TO ASSURE SAFETY AND PROPER COOLING

ALWAYS OPERATE THE UNIT WITH THE COVER

PANELS INSTALLED.

Fans maintain safe operating temperatures in the power
supply by drawing air over the circuit components. The
covers must be on in order to direct the air flow over the
areas that need cooling. In operation, the units air intake
and fan exhaust paths must be clear of any obstructions
that might impede the flow of air.

3.2 Standard Features

A general note on remote interface circuitry and remote
signal grounding:

When usage applications dictate, electrical isolation may
be required when interfacing with high voltage power
supply in question. For power control signals such as
CONTROL POWER, EXTERNAL INTERLOCK, HIGH
VOLTAGE OFF and HIGH VOLTAGE ON isolated
relay contacts should be used. For status signals and
control signals such as HIGH VOLTAGE ON, HIGH
VOLTAGE OFF, EXTERNAL INHIBIT, etc. opto­isolation should be used. When usage applications dictate,
analog programming and monitoring signals may require
isolation via analog isolation amplifiers. All interface
cables should be properly shielded. All power supply
signals should be referenced to the power supplies signal
ground on the rear panel interface connecter.

LOCAL/REMOTE PROGRAMMING: Allows
adjustment of the output voltage, current and power via

the front panel/internal controls (local) or external voltage
sources (remote).

LOCAL CONTROL - In local control (front panel
control), jumpers are installed on rear panel interface
connecter between pin 8 and pin 9 for current control;
between pin 10 and pin 11 for voltage control and
between pin 42 and pin 43 for power control. This will
enable the front panel potentiometers for current/voltage
control and the internal potentiometer for power control.

REMOTE CONTROL - For remote programming, the
above mentioned jumpers are removed and a positive
polarity, ground referenced voltage source is applied to
the pin 8 for current, pin 10 for voltage and pin 42 for
power. Programming signals should be referenced to pin
1, signal ground. Scaling is such that 0-10Vdc
corresponds to 0-100% rated output respectively. See
Figure 3.2A for wiring diagram.

An alternate method of controlling the output remotely is
by using external resistance such as a potentiometer or a
resistor network. For remote control the jumpers are
removed and the desired resistor configuration is
installed. See Figure 3.2B for wiring diagram.

REMOTE MONITORS: Test points are made available
on the rear panel interface connecter for monitoring the
current, voltage and power; pin 5, pin 6 and pin 25
respectively. The test points are always positive
regardless of the output polarity, scaling is such that 0­10Vdc corresponds to 0-100% rated output respectively.
Test points have an output impedance of 1k ohms, ±1%.
See Figure 3.3 for test point designation.

LOCAL/REMOTE CONTROL POWER / HIGH
VOLTAGE ON / HV OFF: Allows for command of

CONTROL POWER, HIGH VOLTAGE ON and HIGH
VOLTAGE OFF by either the front panel controls or
external signals via the rear panel external interface
connecter.

LOCAL CONTROL - For local front panel switch
command of the Control Power functionality a maintained
connection between pin 12 and pin 13 is required. Once
connected as outlined above, the front panel CONTROL
POWER switch will alternate latch on/latch off with each
successive pressing of the switch. For local front panel
command of the HIGH VOLTAGE OFF functionality a
maintained connection between pin 14 and pin 15 is
required.

REMOTE CONTROL – Remote control of CONTROL
POWER, HIGH VOLTAGE ON and HIGH VOLTAGE
OFF can be accomplished via the rear panel interface.
The CONTROL POWER is an on-off toggle contact
between pins 12 and 13. With the front panel CONTROL
POWER switch latched in the “ON” position, opening
and closing the connection between pins 12 and pins 13
will allow remote command of the CONTROL POWER

ST/STR/STA MANUAL 8 118107-001 REV J

functionality. HIGH VOLTAGE OFF and HIGH
VOLTAGE ON are controlled by momentary normally
closed, normally open contacts, respectively between pins
14 and 15, and pins 15 and 16. See Figure 3.4 for
recommended interface.

EXTERNAL INHIBIT: The External inhibit allows the
user to inhibit the power supply output without putting the
power supply into the HIGH VOLTAGE OFF mode.
This circuit can be used to generate fast slewing output
waveforms or control high voltage generation as in Laser
and Capacitor discharge applications. The maximum
inhibit rate should not exceed 5Hz. Consult factory for
higher repetition rates or high pulse load applications.
See Figure 3.5 for the recommended interface circuit.

WARNING

IT IS EXTREMELY DANGEROUS TO USE THE

EXTERNAL INHIBIT TO STOP HIGH VOLTAGE

GENERATION FOR THE PURPOSE OF

SERVICING OR APPROACHING ANY AREA OF

THE LOAD CONSIDERED UNSAFE DURING

HIGH VOLTAGE OPERATION

EXTERNAL INTERLOCK: The External Interlock
connections are provided on the rear panel interface
connecter, pin 3 and pin 4, intended for use in the
connection to a customer provided and implemented
external safety switch. The unit will not operate unless
the interlock circuit is closed. If the interlock is not being
used (use is highly recommended), a jumper must be
installed. During high voltage operation, opening the
External Interlock will cause the unit to revert to the
HIGH VOLTAGE OFF mode. Subsequent closing of the
interlock circuit will NOT return the unit to HIGH
VOLTAGE ON mode; this must be accomplished by
depressing the HIGH VOLTAGE ON switch. See Figure

3.6 for the recommended interface circuit.
ARC DETECT / ARC QUENCH /ARC COUNT: The

ARC Intervention Circuitry senses dynamic arcing or
discharge conditions present at the output load with a
wide bandwidth current transformer coupled to the return
side of the high voltage multiplier.

The instant an arc is detected the generation of high
voltage is electronically inhibited for 200mS; this is called
the ARC Quench time period. After the 200mS period,
the discharged HV output (level dependent upon arc
impedance, arc duration, etc) is ramped back up to the
previous set level. This ramp time is based on the
standard 200mS Slow Start time constant. The ARC
indicator on the front panel will illuminate for
approximately 500mS after each arc has occurred. The
HV INHIBIT indicator will also illuminate for 500mS
indicating that the output is being inhibited (ARC
Quench).

The factory default setting of the Arc Intervention
circuitry is such that if four arcs occur in a ten second
time period the unit will shut down into the POWER
DOWN mode displaying an “ARC Fault”. ARC
parameters can be modified by using the digital interface
and provided GUI but changing these settings can have
serious consequences.

NOTE: Making changes to the ARC Intervention
Circuitry along with excessive arcing of the power supply
can thermally overheat and damage the internal short
circuit limiting assembly. Damage to the power supplies
internal short circuit limiting assembly is consider misuse
of the unit and repairs will not be covered under the
warranty. The ARC Intervention Circuitry is incorporated
and configured to protect the power supply from
excessive arcing, make changes to this circuitry at your
own responsibility and risk.

REMOTE HIGH VOLTAGE ON & REMOTE HIGH
VOLTAGE OFF: Signals are provided for remote

monitoring of the HIGH VOLTAGE ON and HIGH
VOLTAGE OFF status. See Figure 3.7 for recommended
interface.

3.3 Digital Interface (RS-

232/Ethernet)

The ST features standard RS-232 and Ethernet digital
interface capability. Please see Appendix A for complete
details on functionality and operation.

3.4 Reversible Polarity (1-10kV

Units Only) ST/STR Only

1 to 10kV units are inherently reversible by design but
still require a polarity selection to be made at time of
order. These units are air insulated and a simple wiring
change made in the high voltage multiplier section can
convert a positive polarity unit to a negative polarity unit,
or vice versa.

3.5 Multiple Chassis Systems –

ST Only

Additional ST chassis can be connected in parallel to
achieve multiple 12kW increments of power to above and
beyond 100kW’s in a factory configured Master/Slave
arrangement. The Master unit retains its full feature front
panel while the Slave unit(s) have a Blank Front panel.
From an interfacing and functionality standpoint the
multiple chassis system behaves effectively like a single
chassis higher power unit. This technique provides
commonality of physically manageable hardware units
and possibility redundancy further enhancing system
uptime and reliability.

ST/STR/STA MANUAL 9 118107-001 REV J

Typical Multiple Chassis Configuration

Note: 400VAC units do not have an internal circuit breaker. The service connection to these units

must be protected by an appropriately rated and circuit breaker protected power connection.

Figure 3.1 Typical Operating Setup ST

ST/STR/STA MANUAL 10 118107-001 REV J

1

2

3

4

5

6

7

8

9

10

11

DC

DC

Remote
Current

Program

Remote
Voltage

Program

Rear Panel JB1

Zin = 10M ohms

Zin = 10M ohms

Voltage Source:
0 to 10Vdc = 0 to 100% Rated Output

All cables should be shielded with
the shields returned to chassis
ground (E1) of the high voltage
power supply

DC

Remote

Power

Program

42

Zin = 10M ohms

1

2

3

4

5

6

7

8

9

10

11

Remote
Current

Control

Remote
Voltage

Control

Rear Panel JB1

Zin = 10M ohms

Zin = 10M ohms

Potentiometer Settings:
Fully Counterclockwise = Zero Output
Fully Clockwise = 100% of Rated Output

All cables should be shielded
with the shields returned to
chassis ground (E1) of the
high voltage power supply.

50k Ohm50k Ohm

+10Vdc

Power Supply Ground

42

Remote

Power

Control

50k Ohm

Zin = 10M ohms

Figure 3.2A Wiring Diagram for Remote Programming via Voltage Source

____________________________________________________________________________________

ST/STR/STA MANUAL 11 118107-001 REV J

Figure 3.2B Wiring Diagram for Remote Programming via External Resistance

1

2

3

4

5

6

7

Rear Panel

JB1

Zout = 1k ohm, ±1%

Zout = 1k ohm, ±1%

Power Supply Ground

MM

+ +

--

Current
Monitor

Voltage

Monitor

25

M

+

-

Power

Monitor

Zout = 1k ohm, ±1%

Figure 3.3 Remote Monitor Test Point Designations

It is recommended to use relay contacts for S1, S2 and S3.
Relays should be located as close as possible to the high
voltage power supply. Coils should be driven from
isolated sources. Signals are at ~24V, 100mA max, and
are only to be used for contact closure.

S1 must be closed to enable HIGH VOLTAGE ON.
Momentary closure of S2 will enable HIGH VOLTAGE
ON.

Opening S1 will disable HIGH VOLTAGE ON and
switch the unit to the HIGH VOLTAGE OFF mode.

ST/STR/STA MANUAL 12 118107-001 REV J

Figure 3.4 Remote Control of Power ON, High Voltage ON and High Voltage OFF

Figure 3.5 External Inhibit Interface Circuit

____________________________________________________________________________________

Figure 3.6 External Interlock Interface Circuit

ST/STR/STA MANUAL 13 118107-001 REV J

Figure 3.7 Remote High Voltage ON and Remote High Voltage OFF Indicator

Figure 3.8 Remote Overvoltage Adjust Interface

ST/STR/STA MANUAL 14 118107-001 REV J

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

+24Vdc @ 100mA, maximum

Voltage Mode Status

Current Mode Status

Power Mode Status

Interlock Closed Status

Over Power Fault

Over Voltage Fault

Over Current Fault

System Fault

RGLT Error Fault

ARC

Over Temp Fault

AC Fault

General Purpose

Optocoupler

JB1 Rear Panel

100Ω

100Ω

100Ω

100Ω

100Ω

100Ω

100Ω

100Ω

100Ω

100Ω

100Ω

100Ω

R Limit

Signals are 35Vdc @ 10mA, maximum.

R Limit must be selected to limit current ≤ 10mA.

Power Supply

Internal Circuitry

Customer

External Circuitry

All cables should be shielded with the

shields returned to chassis ground (E1) of

the high voltage power supply.

24Vdc lamps or relays may replace the

optocouplers shown. Whatever devices

employed they should be located as close as

possible to the high voltage power supply.

Figure 3.9 Remote Status and Fault Indicator Interface

ST/STR/STA MANUAL 15 118107-001 REV J

Pin

Signal

Parameters

1

Power Supply Common

Power Supply Ground

2

Reset/HV Inhibit

Toggle to reset latched faults, Ground = Inhibit, Open = HIGH VOLTAGE ON

3

External Interlock

+24Vdc @ open, <25mA @ closed

4

External Interlock Return

Return for External Interlock. Pins 3 and 4 must be connected to HV enable

5

mA Test Point

0-10Vdc = 0-100% rated output, Zout = 1kΩ, 1%

6

kV Test Point

0-10Vdc = 0-100% rated output, Zout = 1kΩ, 1%

7

+10Vdc Reference

+10Vdc @ 1mA

8

mA Program Input

0-10Vdc = 0-100% rated output, Zin =>10MΩ, jump to pin 8 for local control

9

Local mA Program Output

0-10Vdc = 0-100% rated output, front panel potentiometer

10

kV Program Input

0-10Vdc = 0-100% rated output, Zin =>10MΩ, jump to pin 11 for local control

11

Local kV Program Output

0-10Vdc = 0-100% rated output, front panel potentiometer

12

Remote Power On Output

24Vdc @ open, 2A peak, 1A DC @ closed

13

Remote Power On Return

Return for Remote Power On

14

Remote HV OFF

+24Vdc @ open, 2A peak, 1A DC @ closed, connect to pin 15 for front panel
operation

15

Remote HV OFF/ON Common

Remote HV OFF/ON Common

16

Remote HIGH VOLTAGE ON

+24Vdc @ open, 2A peak, 1A DC @ closed, momentarily connect to pin 15 for
HV enable

17

HIGH VOLTAGE OFFIndicator

+24Vdc @ 25mA = HV OFF

18

HIGH VOLTAGE ON Indicator

+24Vdc @ 25mA = HIGH VOLTAGE ON

19

Power Supply Common

Power Supply Ground

20

+24Vdc Output

+24Vdc @ 100mA, maximum

21

Voltage Mode Status

Open collector, Low = Active, 35V maximum @ 10mA

22

Current Mode Status

Open collector, Low = Active, 35V maximum @ 10mA

23

Power Mode Status

Open collector, Low = Active, 35V maximum @ 10mA

24

Interlock Closed Status

Open collector, Low = Active, 35V maximum @ 10mA

25

Power Test Point

0-10Vdc = 0-100% rated output, Zout = 5kΩ, 1%

26

Spare

27

Spare

28

Remote Overvoltage Adjust

0-10Vdc = 0-105% rated output

29

Over Power Fault

Open collector, Low = Active, 35V maximum @ 10mA

30

Over Voltage Fault

Open collector, Low = Active, 35V maximum @ 10mA

31

Over Current Fault

Open collector, Low = Active, 35V maximum @ 10mA

32

System Fault

Open collector, Low = Active, 35V maximum @ 10mA

33

RGLT Error Fault

Open collector, Low = Active, 35V maximum @ 10mA

34

ARC

Open collector, Low = Active, 35V maximum @ 10mA

35

Over Temp Fault

Open collector, Low = Active, 35V maximum @ 10mA

36

AC Fault

Open collector, Low = Active, 35V maximum @ 10mA

37

Spare

38

Spare

39

Spare

40

Spare

41

Spare

42

Remote Power Program Input

0-10Vdc = 0-100% rated output, Zout = 1kΩ, 1%, jump to pin 43 for local control

43

Local Power Program Output

0-10Vdc = 0-100% rated output, internal potentiometer

44

+5Vdc Output

+5Vdc @ 100mA, maximum

45

+15Vdc Output

+15Vdc @ 100mA, maximum

46

-15Vdc Output

-15Vdc @ 10mA, maximum

47

RS-232 Tx

RS-232 Tx

48

RS-232 Rx

RS-232 Rx

49

RS-232 GND

RS-232 GND

50

Power Supply Common

Power Supply Ground

= Denotes jumper connection for simplified local front panel control

Figure 3.10 JB1 Rear Panel Interface Connecter

ST/STR/STA MANUAL 16 118107-001 REV J

Chapter 4

T

Principles of Operation

he ST series of high voltage power supplies utilizes
sophisticated power conversion technology. A variety

of analog, digital and power conversion techniques
are employed. This Principles of Operation will introduce
the basic function blocks that comprise the ST power
supply. For details on a specific circuit, consult
Spellman’s Engineering Department.

The ST power supply is an AC to DC converter. Within
the power supply, conversions of AC to DC, high
frequency AC, then to high voltage DC take place. By
reviewing functionality of the subassemblies, a basic
understanding of the process can be gained.

WARNING

THE ENERGY LEVELS USED AND GENERATED BY

THE POWER SUPPLY CAN BE LETHAL! DO NOT

ATTEMPT TO OPERATE THE POWER SUPPLY

UNLESS THE USER HAS A SUFFICIENT KNOWLEDGE

OF THE DANGERS AND HAZARDS OF WORKING

WITH HIGH VOLTAGE. DO NOT ATTEMPT TO

APPROACH OR TOUCH ANY INTERNAL OR

EXTERNAL CIRCUITS OR COMPONENTS THAT ARE

CONNECTED OR HAVE BEEN CONNECTED TO THE
POWER SUPPLY. BE CERTAIN TO DISCHARGE ANY
STORED ENERGY THAT MAY BE PRESENT BEFORE

AND AFTER THE POWER SUPPLY IS USED.

CONSULT IEEE RECOMMENDED PRACTICES FOR

SAFETY IN HIGH VOLTAGE TESTING #510-1983.

4.1 Line Rectification and
Filtering

WARNING

LINE VOLTAGE IS PRESENT WHENEVER THE

POWER SUPPLY IS CONNECTED TO THE INPUT LINE

VOLTAGE. BE SURE TO DISCONNECT THE LINE

CORD BEFORE OPENING THE UNIT. ALLOW 5

MINUTES FOR INTERNAL CAPACITANCE TO

DISCHARGE BEFORE TOUCHING ANYTHING

CONNECTED TO LINE REFERENCED CIRCUITRY

Simple three phase rectification provides the DC buss
voltage for the high frequency inverter.

An input line cord, three phase circuit breaker (customer
provided on 400Vac Option units), EMI Filter Assembly,
contactor, inrush bridge rectifier, electrolytic capacitors,
rail inductor and rail capacitor comprise the basic
components required for input line rectification.

The standard line input voltage for the ST Series is 180­264Vac, 50/60Hz. An optional 360-528Vac, 50/60Hz
input voltage is available (400Vac Option). Optional
Single Phase input is available on the STR and STA. If
the user is unsure which input voltage is required, check
the serial tag on the rear of the power supply or consult
Spellman’s Sales Department

The customer provided AC power input is provided to the
unit via the four conductor AC line cord. Circuit
protection is provided by CB1, a fast acting magnetic trip
type circuit breaker. The load side of CB1 is connected to
EMI filter A2. The output of the EMI filter connects to
K1, a three phase contactor. K1 provides fail-safe type
disconnection of the line voltage to the power supply
rectification circuits. K1’s coil is controlled by a variety
of circuit conditions, which will be described later on.
The load side of CB1 is also connected to low voltage
power supply assembly A9, which provides various
voltages for housekeeping and control circuit power.

When contactor K1 is energized, voltage is applied to
isolated bridge rectifier power module CR1, used for line
voltage rectification. The output of CR1 is connected to
aluminum electrolytic capacitors C1 and C2 for line
filtering purposes. Capacitors C1 and C2 are initially
charged through inrush limiting charging resistors which
is located on POWER PWB – A6.

After an appropriate period of time to charge C1 and C2,
relays on POWER PWB – A6 are energized to short out
the inrush limiting resistors. The generated DC buss
voltage is supplied to the inverter circuitry through L2,
L3, L6 and L7. The inductors provide isolation for the
electrolytic capacitors C1 and C2, so the inverter’s high
frequency pulse currents are drawn from the metalized
film high frequency “rail capacitors” C3 and C12.

The POWER PWB – A6 provides the inrush limiting
function via R1, R2, R3 and R4. Relays K1 and K2 short
out the limiting resistors once the initial charging of C1
and C2 is complete. Resistors R7, R8, and R10, R11 form
two feedback divider circuits with terminating resistors
located on the SYSTEM CONTROL PWB – A1. These
impedance limited, low voltage + and – rail feedback
signals are monitored and if any abnormal conditions
appear, circuitry will shutdown the power supply.

ST/STR/STA MANUAL 17 118107-001 REV J

Typically a SYSTEM FAULT and AC FAULT indication
will appear on the front panel if an error in the charging
circuits has occurred.

R5 on the POWER PWB – A6 functions as a bleeder
resistor, which is used to discharge the front end filter
capacitors C1 and C2. DS1 provides visual indication
when DC voltage is present. This indicator should not be
relied on for confirming the presence or absence of the
DC voltage in any situation where user safety is of
concern.

4.2 Inverter

The inverter employs a proprietary, quasi-resonant, pulse
width modulated topology. L1 and L5 are the resonating
inductors. Q1, Q2 Q3 and Q4 are high speed IGBT
isolated power modules. These devices provide high
frequency switching capability to control the flow of
current through the primary of the high voltage step up
transformers. The gate control for the switching devices
is provided by GATE DRIVE PWB A3 and A4. The
control signals are generated by the SYSTEM CONTROL
PWB – A1.

4.3 High Voltage Transformer

The output of the Inverter is connected to the primary of
the High Voltage Transformer. The High Voltage
Transformer is a step-up type. Typical secondary
voltages are in the range of 1kV to 4.5kV depending upon
the units specific maximum output voltage rating.

4.4 High Voltage Assembly

The High Voltage Assembly will vary depending upon
the model ordered. The circuitry typically consists of a
full wave, full bridge, or full wave doubler for voltage
outputs in the range of 1kV to 10kV. The higher voltage
ranges utilize various parallel, series arrangements of a
full wave voltage doubler. For example, the 8kV output
is obtained by connecting a number of full wave voltage
doublers in parallel. The 120kV output is obtained by

connecting a number of full wave voltage doublers in
series.

Output filtering is typically provided by an L-C type
filter. Voltage feedback for regulation and monitoring is
provided by a high bandwidth resistive/capacitive
compensated feedback divider. Current feedback for
regulation and monitoring is provided by a sense resistor
connected at the low voltage end of the High Voltage
output section.

4.5 System Control PWB

The majority of control circuits for power supply controls
are located on the SYSTEM CONTROL PWB – A1. For
trouble shooting and testing purposes, this board can be
easily accessed by removing the screws located on the
side panels near the front panel. The front panel will
hinge down allowing for easy access to the SYSTEM
CONTROL PWB

4.6 Front Panel Assembly

Front Panel CONTROL POWER, HV OFF, HIGH
VOLTAGE ON, switches, voltage and current
programming potentiometers, voltage and current digital
meters, and status indications are connected to the
FRONT PANEL PWB. – A7. The FRONT PANEL PWB
interfaces directly to the SYSTEM CONTROL PWB ­A1.

4.7 Master/Slave Rear Panel
PWB – ST Only

This assembly is only required and installed when more
than one ST chassis is configured in the system. By
configuring chassis in parallel using a Master/Slave
arrangements additional power increments of 12kW’s can
be obtained for each chassis added. This Master/Slave
Rear Panel PWB provided the necessary control signal
connectivity and functionality to operate multiple chassis
in parallel as a single high powered system.

ST/STR/STA MANUAL 18 118107-001 REV J

T

Chapter 5

OPTIONS

He options available for this power supply are
described in this section. Options are specified by
including the option code in the model number as

described in Section 1.5.

5.1 Blank Front Panel BFP

The Blank Front Panel Option removes local control
functionality and metering from the standard front panel.
This is a popular cost saving measure for OEM
applications where the unit will only be controlled
remotely. The local front panel fault diagnostic panel is
retained providing comprehensive power supply
operational information.

5.2 High Stability HS

The standard internal voltage feedback divider is replaced
with a high precision voltage feedback divider providing a
50ppm/°C temperature coefficient.

5.3 High Voltage Cable Length
LL(X)

Custom length high voltage output cables, indicated in
foot measurement units. Various predetermined lengths
are available along with entirely custom lengths; contact
Spellman Sales Department for details.

5.4 360-528Vac Input 400VAC

This option factory configures the ST/STR to operate
from 360-528Vac, three phase, 50/60Hz input power.

5.5 180-264Vac Single Phase
Input (1PH)

This option factory configures STR and STA units to
operate from 180-264Vac, single phase, 50/60Hz input
power.

5.6 Custom Designed Models
X(#)

Units built to customer specifications are assigned an X
number by the factory. If this unit is an X model, a
specification control sheet is added at the end of this
instructional manual. Spellman welcomes the opportunity
to tailor units to fit your requirements or to develop new
products for your applications. Contact the Spellman
Sales Department with your need.

ST/STR/STA MANUAL 19 118107-001 REV J

5.7 Parallel Option Units
(Multiple Chassis Systems – ST
only)

Physically install the units in a cabinet or stack them one
on top the other, typically the Master units is located at
the top to ease access to the local controls on the full
featured front panel. Cabling up the system is similar
regardless of the numbers of Slave chassis. The following
items will be required to connect up each parallel option
unit:

Control Jumper Cable (gray cable, 15 pin D connecters on
each end)
Ground Jumper Cable (green/yellow cable, ring lugs on
each end)
High Voltage Jumper Cable (black cable, HV connecter
on each end)
Terminator Plug (black plastic clam shell, 15 pin D
connecter)

One cable of each type is required for each Slave chassis;
only one terminator plug is required for each system. The
connections are as follows; repeat as needed for additional
Slave Chassis:

Control Jumper Cable – Connect one side to JB3 of the
Master chassis, connect the other side to JB4 of the Slave
Chassis.

Ground Jumper Cable – Connect one side to E1 ground
stud on the Master chassis, connect the other side to E1
ground stud of the Slave chassis. ***Connect the

customer provided “System Ground Cable” and the
customer provided “Load Return Cable” to the E1 ground

stud on the back of the Master Chassis. Please see Typical

Operating Setup ST figure for required ground
connections***

High Voltage Jumper Cable – Connect one side to J1 of
the Master chassis; connect the other side to J1 of the
Slave Chassis. Connect the terminated side of the High
voltage output cable to J2 of the Slave chassis; connect
the unterminated side to the load as applicable.

Terminator Plug– Plug the Terminator Plug into JB3 of
the Slave Chassis.

The instructions above are for a two chassis Master/Slave
unit, but these instructions can be used for systems with
any number of Slave units keeping these two points in
mind:

●The High Voltage Output Cable always exists from the

“last” Slave unit

●The Terminator Plug is always connected to the JB3

connecter of the “last” Slave unit.

See the annotated photograph of the wiring connections
for a 3 chassis system (Master/Slave1/Slave2) that
follows these instructions.

Cooling Note:
For proper cooling, and to maximize product life span, a

minimum of 1U (1.75”) rack space should be provided

above and below each chassis, and between chassis of
multi-chassis systems. This will allow air circulation, and
also reduce heating effects on other equipment in the
cabinet.

ST/STR/STA MANUAL 20 118107-001 REV J

ST/STR/STA MANUAL 21 118107-001 REV J

Chapter 6

T

WARNING

WARNING

MAINTENANCE

his section describes periodic servicing and
performance testing procedures.

THIS POWER SUPPLY GENERATES VOLTAGES

THAT ARE DANGEROUS AND MAY BE FATAL.

OBSERVE EXTREME CAUTION WHEN WORKING

WITH HIGH VOLTAGE.

6.1 Periodic Servicing

Approximately once a year (more often in high dust
environments), disconnect the power to the unit and
remove the top cover. Use compressed air to blow dust
out of the inside of the unit. Avoid touching or handling
the high voltage assembly. Be sure that the fan is not
obstructed and spins freely. The fan has sealed bearings
and does not need lubrication. Be sure to replace the
cover before operating for proper cooling.

Turn the chassis over and remove the bottom cover. Use
compressed air to blow dust out. NOTE: On 10kV and
below, an air insulated high voltage section is used.
Avoid touching or handling the high voltage assembly.
Be sure to replace the bottom cover before operating the
unit.

High voltage test procedures are described in Bulletin
STP-783, available by clicking the following link

Standard Test Procedures for High Voltage Power
Supplies. Test equipment, including an oscilloscope, a

high impedance voltmeter, and a high voltage divider
(such as the Spellman HVD-100) is needed for
performance tests. All test components must be rated for
applicable operating voltage.

6.3 High Voltage Dividers

6.2 Performance Test

HIGH VOLTAGE IS DANGEROUS. ONLY

QUALIFIED PERSONNEL SHOULD PERFORM

THESE TESTS.

ST/STR/STA MANUAL 22 118107-001 REV J

High voltage dividers for precise measurements of output
voltage with accuracy up to 0.1% are available from
Spellman. The HVD-100 is used for voltages up to
100kV, the HVD-200 measures up to 200kV and the
HVD-400 measures up to 400kV. The Spellman HVD
divider is designed for use with differential voltmeters or
high impedance digital voltmeters. The data sheet for

Spellman’s series of HVD dividers can be viewed by

clicking here.

Chapter 7

C

REPLACEMENT PARTS

7.1 Replacement Parts

ontact the Spellman Customer Service Department
for parts lists for specific models.

Spellman provides parts and subassemblies for its high
voltage power supplies but recommends that only
qualified personnel perform repairs. High voltage is
dangerous; even minor mistakes in repairs can have
serious consequences.

When requesting parts, please provide the complete
model number and serial number of the power supply in
question.

7.2 Correspondence and

Ordering Spare Parts

Each Spellman power supply has an identification label
on the rear of the chassis that bears its model and serial
number.

When requesting engineering or applications information,
please state the model and serial number of the power
supply. If specific components or circuit sections are
involved in the inquiry, it is helpful to indicate the
component symbol number(s) shown on the applicable
schematic diagram.

When ordering spare parts, please specify the part’s

description, the part’s reference designation or part

number, and the model and serial number of the unit.

ST/STR/STA MANUAL 23 118107-001 REV J