Technical information
Last changed on: 16.01.2020

NHQ High Voltage Power Supplies
High Precision Single/Dual Channel HV Module in NIM Standard
•
•
•
•
•
•
•
•

1/2 channels, 2 / 3 / 4 / 5 / 6 kV and customized versions
LCD for voltage and current display
switchable polarity
very low ripple and noise
front panel control with high precise 10-turn potentiometers
hardware voltage and current limits with 10% step
RS232, analog I/O
programmable parameters (current trip, ramp speed etc.)

www.iseg-hv.com

Document history
VersionDate

Major changes

3.0

16.01.2020

High Precision versions removing, 8kV and 10kV versions discontinued, Notes revised, safety
information, glossary

2.2

19.01.201801.10.2018

High Precision versions discontinued
Notes revised

2.1

20.09.2017
21.11.2017

Technical data: Vset Control information added, Warranty notice fixed,
Accuracy Current Measurement for Option L added

2.0

28.02.2017

Relayouted version

Disclaimer / Copyright
Copyright © 2020 by iseg Spezialelektronik GmbH / Germany. All Rights Reserved.
This document is under copyright of iseg Spezialelektronik GmbH, Germany. It is forbidden to copy, extract parts, duplicate forany kind of publication without a written permission of iseg Spezialelektronik GmbH. This information has been prepared forassisting operation and maintenance personnel to enable efficient use.
The information in this manual is subject to change without notice. We take no responsibility for any mistake in the
document. We reserve the right to make changes in the product design without reservation and without notification to
the users. We decline all responsibility for damages and injuries caused by an improper use of the device.

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Safety
This section contains important security information for the installation and operation of the device. Failure to follow safety
instructions and warnings can result in serious injury or death and property damage.
Safety and operating instructuions must be read carefully before starting any operation.
We decline all responsibility for damages and injuries caused which may arise from improper use of our equipment.

Description of the safety instructions
DANGER!
“Danger!” indicates a severe injury hazard. The non-observance of safety instructions marked as “Danger!” willlead to possible injury or death.
DANGER!

WARNING!
“Warning!” indicates an injury hazard. The non-observance of safety instructions marked as “Warning!” could
lead to possible injury or death.
WARNING!

CAUTION!
Advices marked as “Caution!” describe actions to avoid possible damages to property.

CAUTION!

INFORMATION
Advices marked as “Information” give important information.

INFORMATION

Read the manual.

Attention high voltage!

Important information.

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Intended use
The device may only be operated within the limits specified in the data sheet. The permissible ambient conditions (temperature,humidity) must be observed. The device is designed exclusively for the generation of high voltage as specified in the data sheet.
Any other use not specified by the manufacturer is not intended. The manufacturer is not liable for any damage resulting from
improper use.

Qualification of personnel
A qualified person is someone who is able to assess the work assigned to him, recognize possible dangers and take suitablesafety measures on the basis of his technical training, his knowledge and experience as well as his knowledge of the relevant
regulations.

General safety instructions•

Observe the valid regulations for accident prevention and environmental protection.

•

Observe the safety regulations of the country in which the product is used.

•

Observe the technical data and environmental conditions specified in the product documentation.

•

You may only put the product into operation after it has been established that the high-voltage device complies withthe country-specific regulations, safety regulations and standards of the application.

•

The high-voltage power supply unit may only be installed by qualified personnel.

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Important safety instructions
WARNING!
To avoid injury of users it is not allowed to open the unit. There are no parts which can be maintained by users
inside of the unit. Opening the unit will void the warranty.
WARNING!

WARNING!
The high-voltage cable must be professionally connected to the consumer/load and the connection insulatedwith the appropriate dielectric strength. Do not power the consumer/load outside of its specified range.
WARNING!

WARNING!
Before connecting or disconnecting HV cables or any operation on the HV output or the application, the unit has
to be switched off and discharge of residual voltage has to be finished. Depending on application residual
voltages can be present for long time periods.
WARNING!

WARNING!
Do not operate the unit in wet or damp conditions.

WARNING!

WARNING!
Do not operate the unit in an explosive atmosphere.

WARNING!

WARNING!
Do not operate the unit if you suspect the unit or the connected equipment to be damaged.

WARNING!

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CAUTION!
When installing the units, make sure that an air flow through the corresponding air inlet and outlet openings ispossible.
Caution!

INFORMATION
Please check the compatibility with the devices used.

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Table of Content
Document history
Disclaimer / CopyrightSafetyDescription of the safety instructions
Intended use
Qualification of personnel
General safety instructions
Important safety instructions

2
2
3
3
4
4
4
5

1 General description

8

2 Technical Data

9

3 NHQ Description

11

3.1 High Voltage Supply
3.2 Digital control unit
3.3 Filter

11
11
12

4 Handling13

5 Control elements

14

6 Dimensional drawings

16

7 PIN assignments

17

7.1 Analog I/O
7.2 RS 232

1717

8 Connectors and cables

18

9 Accesories

19

10 Order guides

19

11 Appendix

19

12 Glossary

20

13 Warranty & Service

21

14 Disposal

21

15 Manufacturer´s contact

21

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1 General description
CAUTION!
The devices must only be used in combination with iseg approved crates.

CAUTION!

The established NHQ single/dual channel HV module is cased in compact 1/12 NIM format. The NHQ series HV supplies are front
panel controllable with a precise 10-turn potentiometer per channel for voltage setting and a common LCD for display of voltage
or current. For remote control the NHQ comes with RS232, analog I/O. The voltage ramp is hardware fixed and can be changed inremote operation. The high voltage output is short circuit and overload protected, the INHIBIT function over external digital
signal triggers the HV switch-off.

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2 Technical Data
SPECIFICATIONSLOW COSTSTANDARD

Polarity

Switchable

Ripple and noise (f > 10 Hz)< 50 mVp-p< 2 | 5 | 50 mVp-p-5

Stability − [ΔVout vs. ΔVin]< 3 •10 • Vnom

Stability − [ΔVout vs. ΔRload]-4< 2 • 10 • Vnom

< 5 •10-5• Vnom

Temperature coefficient< 100 ppm / K< 50 ppm / K

LCD Display

4 digits with sign, switch controlled (voltage display in V, current display in µA)

Resolution voltage setting

1V

1V

Resolution voltage measurement
display

1V

Resolution voltage measurement
remote1V–

Resolution current
measurement display

1 µA

Resolution current
measurement remote

1 μA

Accuracy voltage measurement
Accuracy current measurement± (0.05 % • Vout + 0.02 % • Vnom+ 1 digit)± (0.05% • Iout + 0.05% • Inom + 1 digit)

Accuracy current measurement with
option L± (0.05 % • Iout + 0.02 % • Inom+ 1 digit)± (0.5% • Iout + 0.5% • Inom + 1 digit)

Measurement accuracy – The measurement accuracy is guaranteed in the range 1% • Vmode < Vout < Vmode and for 1 year
Voltage ramp hardware
Voltage ramp software

500 V / s
2 − 255 V / s–

Voltage Control switch MANUAL

Upper position: manual control by 10-turn potentiometer

Voltage Control switch REMOTE

Lower position: Control by analog set and monitor voltage
NHQ x12 – x14: Vset/mon = Vout / 400
NHQ x15 - x16: Vset/mon = Vout / 1000

Protection
Analog / Digital Interface
HV connector

INHIBIT (1, hardware V/I limits (10% − steps)
AIO

RS232
SHV l S08

System connector

NIM connector

Inhibit connector

Lemo 1pole: ERN.00.250.CTL

Interface connector

Sub-D9Power requirements Vin± 24 V (< 800mA) and ± 6 V (< 100mA)
Option N24: ± 24 V required only

Case

NIM Standard chassis: NIM 1/12

Operating temperature

0 ... 50 °C

Storage temperature-20 ... 60 °C

Humidity

20 − 80 %, not condensing

Notes:
1)
ext.signal, TTL-Level Low=aktive ➜ Vout = 0
Table 1. Technical data: Specifications

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CONFIGURATIONS
Type

Vnom

Inom

Ripple (mVp-p)

INTERFACE

HV connector

Options>10Hz

STANDARD
NHQ n02M

2 kV

6 mA

2

RS232

SHV / S08

L, N24

NHQ n03M

3 kV

4 mA

2

RS232

SHV / S08

L, N24

NHQ n04M

4 kV

3 mA

2

RS232

SHV / S08

L, N24

NHQ n05M

5 kV

2 mA

5

RS232

SHV / S08

L, N24

NHQ n06L

6 kV

1 mA

5

RS232

SHV / S08

L, N24

NHQ n32M

2 kV

6 mA

2

CAN

SHV / S08

L, N24

NHQ n33M

3 kV

4 mA

2

CAN

SHV / S08

L, N24

NHQ n34M

4 kV

3 mA

2

CAN

SHV / S08

L, N24

NHQ n35M

5 kV

2 mA

5

CAN

SHV / S08

L, N24

NHQ n36L

6 kV

1 mA

5

CAN

SHV / S08

L, N24

NHQ n12M

2 kV

6 mA

50

AIO

SHV / S08

L, N24

NHQ n13M

3 kV

4 mA

50

AIO

SHV / S08

L, N24

NHQ n14M

4 kV

3 mA

50

AIO

SHV / S08

L, N24

NHQ n15M

5 kV

2 mA

50

AIO

SHV / S08

L, N24

NHQ n16L

6 kV

1 mA

50

AIO

SHV / S08

L, N24LOW COST

Notes:
n − Number of channels (1 or 2)
Table 2. Technical data

OPTIONS / ORDER INFO

INFO

±24 V SUPPLY ONLY

±24 V = N24

LOWER OUTPUT CURRENT

L (100 μA)

EXAMPLEN 102 L

Table 3. Technical data: Options and order information

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3 NHQ Description
3.1 High Voltage Supply
For the high voltage generation a patented highly efficient resonance converter circuit is used, which provides a sinusoidal
voltage with low harmonics for the HV-transformer. For the high voltage rectification high speed HV-diodes are used. A highvoltage switch, connected to the rectifier allows the selection of the polarity. The consecutive active HV-filter damps the residual
ripple and ensures low ripple and noise values as well as the stability of the output voltage. A precision voltage divider is
integrated in the HV-filter to provide a feedback voltage for the output voltage control, an additional voltage divider supplies thesignal for the maximum voltage monitoring. A precision control amplifier compares the feedback voltage with the set value givenby the DAC (remote control) or the potentiometer (manual control). Signals for the control of the resonance converter and thestabilizer circuit are derived from the result of the comparison. The two-stage layout of the control circuit results in an output
voltage, stabilized with very high precision to the set point.
Separate security circuits prevent exceeding the front-panel switch settings for the current I max and voltage Vmax limits.
A monitoring circuit prevents malfunction caused by low supply voltage.
The internal error detection logic evaluates the corresponding error signals and the external INHIBIT signal and impacts theoutput voltage according to the setup. In addition this allows the detection of short over currents due to single flashovers.

3.2 Digital control unit
A micro controller handles the internal control, evaluation and calibration functions of both channels. The actual voltages andcurrents are read cyclically by an ADC with a connected multiplexer. The readings are processed and displayed on the 4 digit LCD.
The current and voltage hardware limits are retrieved cyclically several times per second. A reference voltage source provides aprecise voltage reference for the ADC and the control voltage for the manual operation mode of the unit.
In the computer controlled mode the set values for the corresponding channels are generated by a 18-Bit DAC.

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3.3 Filter

Figure 1: Block diagram

A special feature of the unit is a tuned filtering concept, which prevents perturbation of the unit by external electromagnetic
radiation, as well as the emittance of interferences by the module. A filtering network for the supply voltages is located next totheir connectors, the converter circuits of the individual channels are protected by additional filters. The high-voltage filters arehoused in individual metal enclosures to shield even minimal interference radiation.

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4 Handling
The NIM connector, the HV-outputs and the 9 pin female Sub-D connector for the RS 232 or Analog I/O interface are located on
the rear panel. Before the unit is powered the desired output polarity must be selected by the rotary switch on the cover side.
The chosen polarity is displayed by a LED on the front panel and a sign on the LCD.
CAUTION!
It is not allowed to change the polarity under power!

CAUTION!
If the switch setting is undefined (not at one of the end positions) high voltage cannot be switched on.
High voltage output is switched on with the HV-ON switch at the front panel. The viability is signaled by the yellow LED.
CAUTION!
If the CONTROL switch is in upper position (manual control), high voltage is generated at the HV-output on therear side, started with a ramp speed from 500 V/s (hardware ramp) to the set voltage chosen via the 10-turnpotentiometer.
CAUTION!

This is also the case, if RS232 control is switched over to manual control while operating.

Output voltage in [V] or output current in [μA] will be displayed on the LCD depending on the position of the Measuring switch.
For two channel units the Channel switch selects whether channel (A) or channel (B) is displayed.
In the manual control mode the output voltage can be set via 10-turn potentiometer in a range from 0 to the maximum voltage.
If the CONTROL switch is switched over to remote control, the DAC takes over the last set output voltage of the manual control.
The output voltage can be changed remotely with a programmable ramp speed (software ramp) from 2 to 255 V/s in a range
from 0 to the maximum voltage.
The maximum output current for each channel (current trip) can be set via the remote interface in units of the resolution of theupper measurement range. If the output current exceeds the programmable limit, the output voltage will be shut off
permanently by the software. A recovery of the voltage is possible after ”Read status word” and then ”Start voltage change” via
serial interface. If ”Auto start” is active, ”Start voltage change” is not necessary.
The maximum output voltage and current can be selected in 10%-steps with the rotary switches V max and Imax (switch dialed to 10
corresponds to 100%) independently of programmable current trip. The red error LED on the front panel signals if the output
voltage or current approaches the limits.
The KILL switch specifies the response on exceeding limits or on the external protection signal at the INHIBIT input as follows:
Switch to the right position: (ENABLE KILL)
When exceeding Imax or in the presence of an INHIBIT signal (Low=active) the output voltage will be shut off permanently without
ramp. The output voltage is only restored after switching HV-ON or KILL or ”Read status word” and then ”Start voltage change” by
DAC control. If ”Auto start” is active, ”Start voltage change” is not necessary.
Note:
If a capacitance is effective at the HV-output or when using a high voltage ramp speed (hardware ramp) under high loads, thenthe KILL function may be triggered by the capacitor charging currents. In this case smaller output voltage change rates (softwareramp) should be used or ENABLE KILL should only be selected once the set voltage is reached at the output.
Switch to the left position: (DISABLE KILL)
The output voltage is limited to Vmax, the output current to Imax respectively; INHIBIT shuts the output voltage off without ramp, theprevious voltage setting will be restored with hard- or software ramp once INHIBIT no longer being present.

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5 Control elements
ELEMENT #DESCRIPTION

1

4 digit LC display

2

Channel switch3

Measurement switch

4

Voltage limit rotary switch

5

Current limit rotary switch

6

Error indicator LED

7

10 – turn potentiometer

8

HV-On indicator LED

9

HV-On switch

10

Control switch

11

Polarity indicator LEDs

12

KILL switch

13

INHIBIT input

Figure 2: Frontpanel

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Figure 3: Polarity Switch – Side view

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6 Dimensional drawings

Figure 4: Dimensional drawing – NHQ 1 channel

Figure 5: Dimensional drawing – NHQ 2 channels

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7 PIN assignments
7.1 Analog I/O
PIN

DESCRIPTION

1

VSETA

Set voltage channel − A

VMONA

Monitor voltage channel − A

GND

Ground

VSETB

Set voltage channel − B

VMONB

Monitor voltage channel − B

2
3
4
5
6
7
8
9
Table 4. PIN assignment Analog I/O

7.2 RS 232
Signal RS 232

HV-supply Sub-D9

RxD

Int.

PC Sub-D9

PC Sub-D25

2

2

3

TxD

3

3

2

GND

5

5

7

Connection 3-lead cable4┐ (bridged)

420┐ (bridged)6┤ (bridged)66┤ (bridged)8┘ (bridged)85┘ (bridged)

Table 5. PIN assignment RS232

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8 Connectors and cables
HV CONNECTOR ASSIGNMENTS
Name

SHV

S08

FigureCONNECTOR ASSIGNMENTSName

INHIBITDSUB9

FigureTable 6. Connector and pin assignments

CONNECTORS PART NUMBERS (manufacturer code / iseg accessory parts item code)
POWER SUPPLY SIDECABLE SIDESHV (ROSENBERGER)
Socket

57S501-200N3

Connector

57K101-006N3 / Z590162

Connector

R317.005.000 / Z592474

Connector

FFA.00.250.CTAC31 / Z200793

S08 (RADIALL)
Socket

R317.580.000
LEMO 1pol.

Socket

ERN.00.250.CTL

Tabelle 7.Connectors part number information

CABLE ORDER GUIDEPOWER SUPPLY SIDECONNECTOR

CABLE
CODE

CABLE DESCRIPTIONLOAD SIDECONNECTOR

ORDER CODE
LLL = length in m (1

SHV

04

HV cable shielded 30kV (HTV-30S-22-2)

open

SHV_C04-LLL

S08

04

HV cable shielded 30kV (HTV-30S-22-2)

open

S08_C04-LLL

1)Length building examples: 10cm ➜ 0.1, 2.5m ➜ 2.5, 12m ➜ 012, 999m ➜ 999

Tabelle 8.Guideline for cable ordering

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9 Accesories
CAUTION!
Only use genuine iseg parts like power cables and terminators for stable and safe operation.

CAUTION!

ACCESSORY ITEMORDER ITEM CODESHV coupler screw for RG58

Z590162

SHV coupler screw for > 5kV

Z592474

1-pin LEMO connector, FFA.00.250.CTAC31

Z200793

Tabelle 9. Accessory

10

Order guides

CONFIGURATION ORDER GUIDE (item code parts)
N

1

0

20

xxx

0

NIM
SeriesNumbers ofchannels

Class

Vnom

Options

Customized Version

0 = Standard
1 = Low Cost

two significante digits • 100VFor Examle: 20 = 2000V

See for moredetails under2 Technical Data

00 = none

Table 10. Item code parts for different configurations

11

Appendix

For more information please use the following download links:
This document
http://download.iseg-hv.com/SYSTEMS/NIM/NHQ/iseg_datasheet_NHQ_en.pdf
RS232 Programmers-Guide
http://download.iseg-hv.com/SYSTEMS/NIM/NHQ/NHQ-RS-232-Programmers-Guide.pdf

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12

Glossary

SHORTCUT

MEANING

Vnom

nominal output voltage

Voutoutput voltage

Vset

set value of output voltage

Vmon

monitor voltage

Vmeas

digital measured value of voltage

Vp-ppeak to peak ripple voltage

Vininput / supply voltage

Vtype

type of output voltage (AC, DC)

Vrefinternal reference voltage

Vmax

limit (max.) value of output voltage∆Vout – [∆Vin]deviation of Vout dep. on variation of supply voltage∆Vout – [∆Rload]

deviation of Vout dep. on variation of output load

Vbounds

Voltage bounds, a tolerance tube Vset ± Vbounds around Vset.

Inomnominal output current

Iout

output current

Iset

set value of output current

Imonmonitor voltage of output current

Imeas

digital measured value of current

Itrip

current limit to shut down the output voltage

Iin

input / supply current

Imax

limit (max.) value of output current

IlimitCurrent Limit.

Ibounds

Current bounds, a tolerance tube Iset ± Ibounds around Iset.

Pnomnominal output powerPininput power

Pin_nomnominal input powerTtemperature

TREF

Reference temperatureON

HV ON/OFF/ON

HV OFF/ON

CH

channel(s)HVhigh voltage

LV

low voltage

GNDsignal ground

INH

Inhibit

POL

Polarity

KILL

KillEnable

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13

Warranty & Service

This device is made with high care and quality assurance methods. The factory warranty is up to 36 months. Please contact theiseg sales department if you wish to extend the warranty.
CAUTION!
Repair and maintenance may only be performed by trained and authorized personnel.
For repair please follow the RMA instructions on our website: www.iseg-hv.com/en/support/rma
CAUTION!

14

Disposal

INFORMATION
All high-voltage equipment and integrated components are largely made of recyclable materials. Do notdispose the device with regular residual waste. Please use the recycling and disposal facilities for electrical andelectronic equipment available in your country.

INFORMATION

15

Manufacturer´s contact

iseg Spezialelektronik GmbH
Bautzner Landstr. 23
01454 Radeberg / OT Rossendorf
GERMANY
FON: +49 351 26996-0 | FAX: +49 351 26996-21
www.iseg-hv.com | info@iseg-hv.de | sales@iseg-hv.de

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