Burster 24508 User manual

Megohmmeter Model 24508
Page 1
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service
Megohmmeter
Model 24508
Manufacturer:
burster praezisionsmesstechnik gmbh & co kg
Talstraße 1 - 5 P.O.Box 1432
76593 Gernsbach 76587 Gernsbach
Germany Germany
Tel.: [phone] / 6450
Fax.: [phone] / 64588
E-Mail: [e-mail]
www.burster.com
3045-024508EN-5999-071527
© 2020 burster
präzisionsmesstechnik gmbh & co kg
All rights reserved
Valid from: 2020-07-06
OPERATION MANUAL

Megohmmeter
Model 24508
Page 2
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service
Note:
Exclusion of warranty liability for operating manuals
All information in the present documentation was prepared and compiled with great care and reproduced subject
to effective control measures. No warranty is provided for freedom from errors. We reserve the right to make
technical changes. The present information as well as the corresponding technical data can change without notice.
Reproduction of any part of this documentation or its processing or revision using electronic systems is prohibited
without the manufacturer’s prior written approval.
Components, devices and measured value sensors made by burster praezisionsmesstechnik (hereinafter referred
to as „product“) are the results of targeted development and meticulous research. As of the date of delivery, burster
provides a warranty for the proper condition and functioning of these products covering material and production
defects for the period specied in the warranty document accompanying the product. However, burster excludes
guarantee or warranty obligations as well as any liability beyond that for consequential damages caused by improper
use of the product, in particular the implied warranty of success in the market as well as the suitability of the product
for a particular purpose. Furthermore, burster assumes no liability for direct, indirect or incidental damages as well
as consequential or other damages arising from the provision and use of the present documentation.

Megohmmeter Model 24508
Page 3
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service

Megohmmeter
Model 24508
Page 4
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service

Megohmmeter Model 24508
Page 5
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service
Contents
Page
Safety instructions............................................................................. 9
1. General information........................................................................... 11
1.1 Use ..................................................................................................... 11
1.2 Description .......................................................................................... 11
1.3 Block diagram...................................................................................... 12
2. Preparations for use .......................................................................... 13
2.1 Unpacking the unit............................................................................... 13
2.2 Usingtheequipmentforthersttime ................................................. 13
2.3 Supply voltage ..................................................................................... 13
2.4 Mains fuse............................................................................................ 14
2.5 Power supply and signal-cable connectors ........................................ 14
2.6 Functional test ..................................................................................... 16
2.7 Calibration............................................................................................ 16
2.8 Storage ................................................................................................ 16
3. Controls and connections................................................................. 17
3.1 Button functions .................................................................................. 17
3.2 Description of connectors.................................................................... 18
4. Manual operation ............................................................................... 19
4.1 General instructions............................................................................. 19
4.2 Setting the measurement time............................................................. 20
4.3 Threshold switch.................................................................................. 20
4.4 Measurement start............................................................................... 20
4.5 Error messages.................................................................................... 21
4.6 Example of a measurement in autorange mode.................................. 21
4.7 Overview of operation.......................................................................... 23
5. Remote control .................................................................................. 27
5.1 Controlling the unit remotley................................................................ 27
5.2 Pin connections for the RS232 interface ............................................. 27
5.3 Command code for the RS232 interface ............................................. 28
5.3.1 Transit commands to the
megohmmeter type 24508 via RS232................................... 28
5.3.2 Response from type 24508 ................................................... 29
5.4 Programming example......................................................................... 30
5.5 Execute of the test program ................................................................ 35
5.6 The answer to interface problems ....................................................... 35
6. Maintenance and customer service................................................. 37
6.1 Maintenance ........................................................................................ 37
6.2 Customer service................................................................................. 37
6.3 Factory warranty .................................................................................. 38
6.4 Cleaning............................................................................................... 38
7. Technical data .................................................................................... 39
8. Appendix............................................................................................. 41

Megohmmeter
Model 24508
Page 6
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service

Megohmmeter Model 24508
Page 7
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service
This equipment complies with the following
 productspecications
Safety: CEI 1010-1 / EN 61010-1 Class I protection
Operating voltage: 230 V cat. II
EMC: Electromagnetic compatibility
Interference emission: EN 55011 Group 1 Class
B
Interference immunity: EN 50082-1
CEI 1000-4-2 Level 3; CEI 1000-4-3 Level 2
CEI 1000-4-4 Level 2

Megohmmeter
Model 24508
Page 8
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service

Megohmmeter Model 24508
Page 9
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service
Safety requirements and operating
instructions
n Forreasonsofsafety,thisequipmentmustonlybeusedbysuitablyqualied
and trained personnel who are aware of the potential hazards.
Read this manual through thoroughly before using the equipment.
nWith regard to the potential hazards associated with using any electric circuit, it
is important that the user is completely familiar with the information concerning
the possible capabilities and applications of this equipment and how it works.
nUnder normal conditions of use, there is absolutely no risk to the user of elec-
tric shock from this equipment. Nevertheless, high voltages can occur during
insulation tests, so all safety-related instructions must be followed to the letter.
The various operations must be performed with care and attention by the user.
A mistake can have catastrophic results for safety or result in severe damage to
the equipment.
nThe protection provided by this equipment may be reduced if it is not used in ac-
cordance with the instructions in this manual, or if the user has made technical
changes without authorization.
nThis equipment has class Ιprotection (protected by equipment grounding con-
ductor). The equipment is connected to the potential equalization system of the
test room via the equipment grounding conductor, which must be tested to VDE
0100 part 410 (IEC 364-4-41).
Before using the equipment, always check that the power lead is undamaged. If
the mains fuse has blown, it must be replaced by a fuse with an identical rating;
disconnect the equipment from the mains and remove all cables from the front
panel before replacing the fuse.
nThis equipment must be installed in a properly ventilated room, and its ventilation
systems must not be blocked up or covered. If heat cannot dissipate properly
then there is a risk of impaired operation of the equipment and a reduced service
life.

Megohmmeter
Model 24508
Page 10
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service
nNever use or operate electrical equipment if either the equipment or you are wet,
not even if just your hands or feet are wet.
nIn the event of faults, switch off the voltage immediately and pull out the plug.
nNotify any damage or anything unusual on electrical equipment to a skilled person
immediately.
nFind out about the relevant maintenance information for this equipment; please
refer to the „Maintenance and Customer Service“ chapter.
nUse the test leads provided to connect the object under test to the megohm-
meter.
nDuring insulation-resistance testing, never touch the test probes or the object
under test (high voltage).
nMeasuring the insulation resistance on a capacitive object can be dangerous
for the user. A built-in relay ensures that the capacitive discharge of the element
under test has a time constant of less than 0.1 s for 1 µF. It is forbidden to touch
the object before making sure that it has been completely discharged.
nBefore measuring the insulation resistance it is essential to check that there is
no voltage across the terminals of the object under test.
n Conrmingthe“MEASURE:...”function(usingbutton[2])switchesonthevolt-
age source. Certain safety precautions must therefore be followed depending
on the programmed test voltage.
nKey to symbols used:
Warning – see operating manual
Warning - Dangerous voltage - risk of electric shock
Ground terminal

Megohmmeter Model 24508
Page 11
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service
General informa-
tion
1.1 Use
Thisequipment,givenitsspecication,canbeusedforallcommonapplica-
tions. It is particularly suitable for resistance measurements across insulators
suchascableinsulation,lms,textiles,oorcoverings,insulatingoilsetc.
With test voltages of 45 V, 100 V, 250 V and 500 V, the unit complies with most
test regulations such asDIN 51953, DIN 53482, DIN 54345.
The guard circuit can be used to measure individual resistances in a delta con-
nection e.g. a twin-core cable with common screening, or measuring insulators
in a guard ring measuring cell.
The measuring range can be selected manually or automatically. Fast serial
measurements can be performed using the integral threshold switch. If the
reading lies below an adjustable limit, the threshold monitor trips and enables
an isolated relay output. The megohmmeter is suitable for both laboratory and
industrial use.
1.2 Description
The digital megohmmeter type 24508 is a microprocessor-controlled instru-
ment for measuring insulation resistances. The unit has a clear layout and is
housed in a rugged metal case. The individual components are easily acces-
sible, providing ideal servicing conditions.
The measuring range extends from 50 kΩto 10 TΩor 5 pA to 10 mA for test
voltages of 45 V, 100 V, 250 V and 500 V.
The two-line LCD display and compact menu-driven operation helps the user
to set up the unit easily. Of course all settings can also be made via the RS232
interface. The connector for the isolated threshold output and the external
test-start/stop is located on the rear panel.
1. General information

Megohmmeter
Model 24508
Page 12
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service
1.3 Block diagram
This unit contains a voltage generator, which outputs a regulated voltage, a measuring unit covering 8 measuring ranges, and one
alphanumeric display. A microprocessor controls the various functions such as setup menus, voltage ranges, measuring ranges, computations, RS232 interface. It compares the measured value with a target value set by the user, and signals if the measurement lies above or below this value (via an indicator lamp on the front panel and using a changeover contact accessible on a rear-panel connector).
Principle of operation
General informa-
tion

Megohmmeter Model 24508
Page 13
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service
2. Preparations for use
Preparations for
use
2.1 Unpacking the unit
The unit weighs 2.1 kg and is packaged accordingly to protect against
shock.
Carefully unpack the unit and verify that all items are present.
This normally includes: 1 digital megohmmeter type 24508
1 power lead
1 pair of instrument leads
1 copy of this manual.
Inspect the unit carefully for damage.
If you suspect that the unit has been damaged during shipping, notify the de-
livery company within 72 hours.
The packaging should be retained for examination by a representative of the
manufacturer and/or the delivery company.
The megohmmeter type 24508 should be shipped only in its original packaging
or in packaging capable of providing an equivalent degree of protection.
2.2 Usingtheequipmentforthersttime
Check that the correct supply voltage 230 V/50 Hz is available. Connect the
unit to a standard grounding outlet using the power lead supplied.
Warning: The unit must not be switched on under any circumstances if it
shows signs of damage during shipping.
The case or measurement input can carry life-threatening voltages if the mains
voltage is transferred as a result of damage.
2.3 Supply voltage
The supply voltage is factory set to 230 V~.
Supply voltage: 230 V~ ± 10 %
Frequency range: 50 Hz / 60 Hz
Power consumption: 10 VA
Fuse rating: 0.16 AF

Megohmmeter
Model 24508
Page 14
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service
2.4 Mains fuse
The mains fuse is located blow the mains socket on the rear of the unit.
Make sure that the unit is fully disconnected from the electrical mains before
changing the fuse. (Remove the power lead from the grounding outlet).
Only use original fuses 5 x 20 mm 0.16 AF for 230 V~.
2.5 Power supply and signal-cable connectors
DIGITAL I/0
Preparations for
use
9-pin min sub-D fe-
male connector
View towards socket
1 - NC
2 - RXD
3 - TXD
4 - DTR
5 - Digital GND (grounded inter-
nally)
6 - NC
7 - NC
8 - CTS
9 - NC
Connector shell : PE (protective
ground) potential
Mating connector : Type 9900-
V209
RS232 interface
1 - Relay common contact
2 - Relay NC contact
3 - Relay NO contact
4 - OV
5- External Start/Stop
Connector shell : PE (protective
ground) potential
Mating connector : Type 9942

Megohmmeter Model 24508
Page 15
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service
Preparations for
use
Rear panel of unit
Comparator Relay output and external Start/Stop
Mains Fuse

Megohmmeter
Model 24508
Page 16
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service
2.7 Calibration
The equipment was calibrated before shipping.
The calibration history of the instruments used for the calibration can be traced to
the government measurement standard in accordance with DIN ISO 9000pp.
The equipment should be recalibrated after a period of about one year.
Calibration must only be performed at the manufacturer’s premises.
2.8 Storage
The unit can be stored at temperatures between - 20°C and +70 °C.
If condensation has formed on the unit, make sure that the unit is completely
dry (including inside) before switching it on.
No further measures are required before use after storage.
2.6 Functional test
After switching on the unit, the following text appears successively on the
display:
Preparations for
use
burster 24508
µA / Megohmmeter
burster 24508
Version B xxxxxxx
RESISTANCE
CURRENT
⇓
⇓

Megohmmeter Model 24508
Page 17
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service
Controls and con-
nections
3.1 Button functions
3. Controls and connections
1
- Power switch
2 - Red button with dual function: 1.Conrmingthemenuselection 2. START/STOP measurement in test menu 3 - Ground PE (protective earth / equipment grounding conductor) 4 - Guard connection for tests on screened cables 5 - Measurement input (X) 6 - Test voltage (U)
7 - Test-voltage indicator lights up when the test voltage is
applied across the connectors
8 - Threshold indicator lights up when the measured value lies
above the set limit
9+10
Cursor function UP/DOWN for selecting the test
parameters
11 - Display for showing the measured value and displaying the
different test menus

Megohmmeter
Model 24508
Page 18
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service
3.2 Description of connectors
Test voltage
Red BNC socket
1 - Plastic insulation
2 - Ground (protective ground)
3 - Voltage output
Measurement input
Black BNC socket
1 - Plastic insulation
2 - Guard (functional ground)
3 - Measurement input
Guard connector
Blue ø 4 mm safety socket
for ø 4 mm safety bunch plug
Ground socket
Green/Yellow ø 4 mm safety socket
for ø 4 mm safety bunch plug
Controls and con-
nections

Megohmmeter Model 24508
Page 19
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service
4. Manual operation
Manual operation
of the unit
4.1 General instructions
Beforeoperatingthe24508andconnectinganyelectricalleads,rststudythe
„Safety requirements and operating instructions“ chapter.
Procedure
- Place the unit on a stable work surface, and observe the directions on proper
ventilation.
- Connecttheunittoamainsoutletttedwithanequipmentgroundingcon-
tact,andpoweruptheunitbypressingthemainsswitch[1].Theilluminated
display indicates that the unit is running. If the display does not come on,
check the electrical connection to the mains and the fuse if necessary (See
„Maintenance and warranty“ chapter)
- Connect the megohmmeter to the object under test according to the type
of measurement to be made (the chapter „General information on the meg-
ohmmeter“ in the appendix contains more details on this).
- Move the cursor in the menu „Resistance/Current“ into the required position
andthenconrmyourselectionwithbutton[2].
Proceed to select the required settings in the subsequent menus.
 Conrmingthe“MEASURE:...”functionswitchesonthevoltagesource.
Certain safety precautions must therefore be followed depending on the
programmed test voltage.
Pressing any control button during a test will abort the test and switch off
thevoltagesource.Pressingoneofthetwoselectionkeys[9]or[10]takes
you back through the various functions.
- We recommend that after each test, you leave the object under test con-
nected to the megohmmeter for a short time to allow the residual voltage
across the terminals of the object under test to decay away (discharge time
about 0.1 s for 1 µF).

Megohmmeter
Model 24508
Page 20
Technical data General informa-
tion
Preparations for
use
Controls and con-
nections
Manual operation
of the unit
Controlling the
unit remotely
Maintenance and
customer service
4.2 Setting the measurement time
A time of up to 999 s (> 16 min.) can be preset in the „Time of Measure“ menu.
Once the measurement time has elapsed, the unit goes automatically into the
stop state, and the value last measured is saved in the display.
The last measured value is transferred via the RS232 interface at the end of
the measurement time.
4.3 Threshold switch
If the measured value exceeds the threshold, i.e. the test object is OK, the
relay closes and the „R LIMIT“ LED on the front panel comes on. An isolated
changeover contact is provided for external processing (max. 48 V, 1 A). The
measured-value display and the test assessment are saved until a new mea-
surement is initiated.
4.4 Starting a measurement
After switching on the unit, it opens in test mode with the parameters last
entered and saved, such as measuring range, test voltage and threshold. The
measurementcanbelaunchedmanuallyusingbutton[2]onthefrontpanelor
via an isolated contact on the rear of the unit.
Manual operation
of the unit