Chauvin Arnoux C.A 6550 User manual

ENGLISH User’s manual
C.A 6550
C.A 6555
MEGOHMMETERS 10 kV AND 15 kV

2
WARNING, risk of DANGER! The operator must refer to these instructions whenever this danger symbol appears.
Equipment protected by double insulation.
Caution! Risk of electric shock.
USB socket.
Earth.
The CE marking indicates conformity with European directives, in particular LVD and EMC.
The rubbish bin with a line through it indicates that, in the European Union, the product must undergo selective
disposal in compliance with Directive WEEE 2002/96/EC. This equipment must not be treated as household waste.
Thank you for purchasing a megohmmeter C.A 6550 or C.A 6555.
For best results from your instrument:
read these operating instructions carefully,
comply with the precautions for use.
Definition of measurement categories:
Measurement category IV corresponds to measurements taken at the source of low-voltage installations.
Example: power feeders, counters and protection devices.
Measurement category III corresponds to measurements on building installations.
Example: distribution panel, circuit-breakers, machines or fixed industrial devices.
Measurement category II corresponds to measurements taken on circuits directly connected to low-voltage installations.
Example: power supply to electro-domestic devices and portable tools.
PRECAUTIONS FOR USE
This instrument and its accessories comply with safety standards IEC 61010-1, IEC 61010-031, and IEC 61010-2-030 for voltages
of 1000V in category IV at an altitude of less than 2000m, indoors, with a degree of pollution of not more than 2.
Failure to observe the safety instructions may result in electric shock, fire, explosion, and destruction of the instrument and of
the installations.
The operator and/or the responsible authority must carefully read and clearly understand the various precautions to be taken
in use. Sound knowledge and a keen awareness of electrical hazards are essential when using this instrument.
If you use this instrument other than as specified, the protection it provides may be compromised, thereby endangering you.
Do not use the instrument on networks of which the voltage or category exceeds those mentioned.
Do not use the instrument if it seems to be damaged, incomplete, or poorly closed.
Before each use, check the condition of the insulation on the leads, housing, and accessories. Any item of which the insulation
is deteriorated (even partially) must be set aside for repair or scrapping.
Use only the leads and accessories supplied. Using leads (or accessories) of a lower voltage or category reduces the voltage
or category of the combined instrument + leads (or accessories) to that of the leads (or accessories).
Use personal protection equipment systematically.
Keep your hands away from the terminals of the instrument.
When handling the leads, test probes, and crocodile clips, keep your fingers behind the physical guard.
As a safety measure, and to avoid interference, do not move and do not handle the leads during measurements.

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CONTENTS
1. COMMISSIONING.................................................................................................................................................................... 4
1.1. Unpacking ...................................................................................................................................................................... 4
1.2. Specifications label ........................................................................................................................................................ 5
1.3. Charging the batteries.................................................................................................................................................... 5
1.4. Adjusting the brightness and contrast ........................................................................................................................... 6
2. DESCRIPTION OF THE INSTRUMENT................................................................................................................................... 7
2.1. Functions........................................................................................................................................................................ 8
2.2. Display............................................................................................................................................................................ 8
2.3. Keypad ......................................................................................................................................................................... 10
2.4. PC software.................................................................................................................................................................. 10
3. PROCEDURE ......................................................................................................................................................................... 11
3.1. Using the leads............................................................................................................................................................. 11
3.2. AC/DC voltage measurement....................................................................................................................................... 12
3.3. Insulation measurement ............................................................................................................................................... 12
3.4. Error indications ........................................................................................................................................................... 20
3.5. DAR (dielectric absorption ratio) and PI (polarization index)........................................................................................ 21
3.6. DD (dielectric discharge index)..................................................................................................................................... 23
3.7. Capacitance measurement .......................................................................................................................................... 25
3.8. Measurement of the residual current............................................................................................................................ 25
4. COMPLEMENTARY FUNCTIONS ......................................................................................................................................... 26
4.1. TEMP key ..................................................................................................................................................................... 26
4.2. ALARM key................................................................................................................................................................... 27
4.3. CONFIG key ................................................................................................................................................................. 27
4.4. DISPLAY key ............................................................................................................................................................... 32
4.5. GRAPH key................................................................................................................................................................... 32
4.6. FILTER key ................................................................................................................................................................... 33
4.7. HELP key...................................................................................................................................................................... 34
5. CONFIGURATION (SET-UP) .................................................................................................................................................. 35
5.1. Restoring the initial configuration................................................................................................................................. 35
5.2. General parameters...................................................................................................................................................... 36
5.3. Measurement parameters ............................................................................................................................................ 36
5.4. Adjustment of the test voltages.................................................................................................................................... 37
5.5. Adjustment of the alarm thresholds ............................................................................................................................. 38
6. MEMORY FUNCTION ............................................................................................................................................................ 39
6.1. Recording of the measurements .................................................................................................................................. 39
6.2. Reading recorded values.............................................................................................................................................. 41
6.3. Erasing the memory ..................................................................................................................................................... 42
6.4. List of coded errors ...................................................................................................................................................... 44
7. DATA TRANSFER SOFTWARE.............................................................................................................................................. 45
8. SPECIFICATIONS................................................................................................................................................................... 46
8.1. Reference conditions.................................................................................................................................................... 46
8.2. Characteristics per function ......................................................................................................................................... 46
8.3. Power supply................................................................................................................................................................ 52
8.4. Environmental conditions............................................................................................................................................. 54
8.5. Construction specification............................................................................................................................................ 54
8.6. Compliance with international standards..................................................................................................................... 54
8.7. Variations in the domain of use .................................................................................................................................... 54
8.8. Intrinsic uncertainty and operating uncertainty............................................................................................................ 55
9. MAINTENANCE...................................................................................................................................................................... 56
9.1. Cleaning ....................................................................................................................................................................... 56
9.2. Metrological check ....................................................................................................................................................... 60
9.3. Repair ........................................................................................................................................................................... 60
9.4. Updating of the internal software................................................................................................................................. 61
10. WARRANTY ......................................................................................................................................................................... 62
11. TO ORDER............................................................................................................................................................................ 63
11.1. Accessories ................................................................................................................................................................ 63
11.2. Replacement parts ..................................................................................................................................................... 63

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1. COMMISSIONING
1.1. UNPACKING
1One power cord 2 metres long for recharging the battery.
2One data transfer software program and one optical-USB cord.
3Two safety leads (red and blue), 3 metres long, with high-voltage plugs at both ends.
4One guarded safety lead (black), 3m long, with high-voltage rear pick-up plugs at both ends.
5One safety lead (blue), 0.5m long, with two high-voltage plugs, one of them with a rear pick-up.
6One carrying bag for the accessories.
7Three crocodile clips (red, black, and blue).
8Two test probes (red and black).
9Five user manuals (one per language) on a CD-ROM.
10 Five safety sheets (one per language).
11 Five specifications labels (one per language).
➀
➃
➁
➂
➇
➈
11
➅
➄
➆
x 5
x 5
PRÉCAUTIONS D’EMPLOI
Cetappareil est protégé contredes tensions accidentelles n’excédant pas 600 V par rapport à la terreen
catégoriede mesure III ou 300 V par rapport à la terre en catégorie de mesure IV.La protection assurée
parl’appareil peut-être compromise si celui-ci est utilisé de façon non spécifiée par le constructeur.
Respectezla tension et l’intensité maximales assignées ainsi que la catégorie de mesure.
Nedépassez jamais les valeurs limites de protection indiquées dans les spécifications.
Respectezles conditions d’utilisation, àsavoir la température, l’humidité, l’altitude,le degré de pollution
etle lieu d’utilisation.
N’utilisezpas l’appareil ou ses accessoires s’ils paraissent endommagés.
Pour le recharge de la batterie, utilisez uniquement le bloc adaptateur secteur fourni avec
l’appareil.
Utilisezdes accessoires de branchement dont la catégorie de surtension et la tension de service
sontsupérieures ou égales à celles de l’appareil de mesure (600 V CAT III).
Touteprocédurede dépannage ou de vérification métrologique doit être effectuée par du personnel
compétentet agréé.
Utilisezles moyens de protection adaptés.

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
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

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ATTENTION,risque de DANGER !
L’opérateurs’engage à consulter la présente notice à chaque fois que ce symbole de
dangerest rencontré.
Appareilprotégé par une isolation double.
Polaritédu connecteur d’alimentation en tension continue.
Lemarquage CE atteste la conformité aux directives européennes.
La poubelle barrée signifie que, dans l’Union Européenne, le produit doit faire l’objet
d’untri sélectif des déchets pour le recyclage des matériels électriques et électroniques
conformémentà la directive WEEE 2002/96/EC.
Définitiondes catégories de mesure :
Lacatégorie de mesure IV correspond aux mesurages réalisés à la source de l’installation basse
tension.
Lacatégorie de mesure III correspond aux mesurages réalisés dans l’installation du bâtiment.
Lacatégorie de mesure II correspond aux mesurages réalisés sur les circuits directement branchés
àl’installation basse tension.
Lacatégorie de mesure I correspond aux mesurages réalisés sur des circuits non reliés directement
auréseau.
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FICHE DE SÉCURITÉ DU C.A 6116 (FR)
Vous venez d’acquérir un contrôleur d’installation C.A 6116 et nous vous remercions de votre
confiance.
Pourobtenir le meilleur service de votre appareil :
lisezattentivement cette notice de fonctionnement,
respectezles précautions d’emploi.


04- 2009
Code691923A01 - Ed. 1
10

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1.3. CHARGING THE BATTERIES
When using the instrument for the first time, start by fully charging the batteries. Charging must be done at a temperature between
0 and 30°C.
> 90 Vac
< 260 Vac
50 / 60 Hz
Set the switch to OFF. Connect the mains cord.
MR
U-STEP
U-RAMP
U-VAR.
U-FIXED
OFF
SET-UP
OFF
Battery 1
Battery 2
2%
12.4 V
1953 mA
26.4°C
00:05:30
3%
11.7V
13 mA
26.7°C
00:05:20
Charging
During the charging, the instrument displays the
following information:
The percentage charge of each of the batteries, their voltages, their
charging currents, their temperatures, and the charging times.
To reduce the power to be supplied and make it possible to use the
instrument during the charging, the batteries are charged alternately
at 2A for 10 seconds. It is for this reason that the charging current
keeps varying.
The text on the side indicates:
Charging = battery being charged,
Full = battery fully charged,
Cold = battery too cold to be charged,
Hot = battery too hot to be charged,
Defect = battery faulty (must be replaced).
1.2. SPECIFICATIONS LABEL
Attach one of the 5 specifications labels, with your appropriate language, on the inside of the lid.

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MR
U-STEP
U-RAMP
U-VAR.
U-FIXED
OFF
SET-UP
SET-UP

> 2s
HELP

HELP
Display Contrast
Backlight
CONTRAST & BACKLIGHT
Press the HELP key for more
than two seconds.
Press the keys to adjust the contrast.
Press the  keys to adjust the brightness.
Press the HELP key to validate.
These adjustments are stored even after the instrument is switched off.
1.5. CHOICE OF LANGUAGE
Before using the instrument, first choose the language in which you want the instrument to display its messages.
Set the switch to SET-UP. Use the keys to select the “language” line. Then use the keys to
choose your language from among those proposed.
Charging time:
between 6 and 10 hours, depending
on the initial charge condition.
Battery 1
Battery 2
Full
Full
100%
11.4 V
15 mA
55.1°C
02:34:41
100%
11.4 V
15 mA
55.1°C
02:34:24
Following prolonged storage, the batteries may be completely discharged. In this case, the first charge may last longer.
Charging when the instrument is in operation is also possible. In this case the symbol flashes.
The charging current then depends on the test voltage and on the resistance measured. If the power necessary for the measurement
exceeds 10W, the batteries are no longer charged.
1.4. ADJUSTING THE BRIGHTNESS AND CONTRAST

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TEMP ALARM CONFIG DISPLAY
MEM
HELP
FILTER GRAPH
110-230V 50/60 Hz
80 VA max
MR
U-STEP
U-RAMP
U-VAR.
U-FIXED
OFF
SET-UP
1000V CAT III
600V CAT IV
( 2500V )
C.A 6555
15kV MEGOHMMETER
2. DESCRIPTION OF THE INSTRUMENT
Charging batteries.
Transfer of data to a PC.
Rotary switch to select a measurement function, SET-UP, or memory read.
To start and stop the measurements.
START/STOP

Arrow keys for browsing in the graphic screen.
ALARM MEM CONFIG DISPLAY
Activation/deactivation of the alarms. Programming of the alarms.
Recording of the measurements.
Configuration of the measurement parameters.
Display of all parameters of a measurement.
TEMP HELP FILTER GRAPH
To refer the measured resistance value to the reference temperature.
Help and backlight key.
Smoothing of the measurements.
Display of the resistance and test voltage curves versus time.
M
Connection terminals.
Graphic screen.

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2.1. FUNCTIONS
C.A 6550 and C.A 6555 megohmmeters are high-end portable measuring instruments intended for the measurement of very high
electrical insulation and resistance values, mounted in a rugged site housing with a cover; they have graphic screens and can
operating on battery or mains power.
The C.A. 6550 makes insulation measurements at voltages up to 10,000V, the C.A. 6555 up to 15,000V.
Their main functions are:
detection and measurement of input voltage, frequency, and current;
quantitative and qualitative insulation measurement:
measurement at a fixed test voltage of 500, 1,000, 2,500, 5,000, 10,000 or 15,000V
dc
;
measurement at an adjustable test voltage between 40 and 15,000V
dc
;
measurement with a voltage ramp from 40 to 1,100V, or from 500 to 15,000V;
measurement with a voltage in steps from 40 to 15,000V;
non-destructive (Early break) test, test stopped at a preset current (Break at I-limit) or Burn-in;
calculation of the DAR, PI, and DD (dielectric discharge index) quality ratios;
calculation of the measured resistance referred to a reference temperature.
measurement of the capacitance of the circuit tested;
measurement of the residual current.
These megohmmeters contribute to the safety of electrical installations and equipment.
Their operation is managed by microprocessors that acquire, process, display, and store the measurements.
They have many advantages, such as:
digital filtering of insulation measurements;
measurement of the voltage;
the programming of thresholds to trigger audible alarms;
the timer for measurement duration checks;
the programming of a limitation of the measurement current;
the plotting of the voltage and resistance curves;
protection of the device by fuse, with detection of defective fuse;
operator safety thanks to the automatic discharging of the test voltage on the tested device at the end of the measurement;
automatic power save mode of the device to save battery power;
indication of battery charge condition;
large graphic display with backlight capability;
a memory to store the measurements, a real-time clock, and a USB interface;
data export to a PC (using the software provided).
2.2. DISPLAY
The display unit is a graphic display with a resolution of 320x240 pixels.
It has built-in back-lighting, which can be controlled by a long press on the key (see §1.4).
2.2.1. EXAMPLE OF DISPLAY BEFORE THE MEASUREMENT
FIXED VOLTAGE
1000 V
Input voltage
Frequency
Input current
Date 2011.05.23
-0.1 V DC
0.2 Hz
112 pA
Time 10:31
BURN
500 V 2500 V
ALARM
Test Run Time 00:02:00
The blinking value can be
modified using the  keys.
Condition of the batteries.
Test with programmed duration. The alarm is active.
Programmed duration of the test.
Value of the external voltage
present on the terminals and its
frequency.
Current flowing between the
terminals. Date and time.
Value of the next lower available
test voltage.
Value of the next higher available
test voltage.
Type of test voltage.
No current limitation
programmed.

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10 100 110 10 10
100 1100 1
kΩMΩGΩTΩ
303.3 MΩ
3.244 µA
Elapsed Time 00:00:48
DF 20s
984 V
ALARM
DH
I-LIM
The measurement smoothing
filtering is active, with a time
constant of 20 seconds.
Value of the insulation resistance.
True value of the test voltage.
Current flowing between the
terminals.
Elapsed time since the beginning
of the measurement.
Value of the insulation resistance
on the bargraph.
2.2.2. EXAMPLE OF DISPLAY DURING THE MEASUREMENT
2.2.3. EXAMPLE OF DISPLAY AFTER THE MEASUREMENT
995 MΩ
528 V 531 nA
Elapsed Time 00:01:12
DAR (30s/60s)
PI (1.0m/10m)
Capacitance
1.00
---
2.201 nF
RANGE E-BRKALARM
Value of the insulation resistance.
True value of the test voltage at
the end of the measurement.
The type of measurement is a
non-destructive test.
Current at the end of the
measurement.
Duration of the measurement.
Ancillary results.
The measurement range is fixed.
The voltage generated is >70V
dc
and therefore dangerous.
The symbol indicates blinking.
If values are undetermined, they are represented by - - - -.
The alarm threshold has been
crossed.
Programmed current limitation.

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2.3. KEYPAD
If the audible signal has not been deactivated in SET-UP, the instrument confirms each key press by an audible beep. If the beep
is more acute, pressing the key is prohibited or will have no effect.
A long press (press maintained for more than two seconds) is confirmed by a second audible beep.
2.4. PC SOFTWARE
This Pc software is used to:
transfer data stored in the instrument,
print customised test protocols in accordance with user needs,
create ExcelTM spreadsheets,
to set the instrument up and control it entirely via the USB link.
The recommended minimum configuration is a PC running XP, Vista, or Windows 7.

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15 kV max
15 kV max
3. PROCEDURE
When they leave the factory, the C.A. 6550 and C.A. 6555 are configured so that they can be used without modifying the parameters.
For most measurements, you simply choose the test voltage and press the START/STOP button.
If you want to modify parameters, most of them can be configured using the CONFIG key, and also in SET-UP.
The SET-UP function allows overall configuration of the instrument independently of which measurement functions are chosen.
The CONFIG key allows configuration of the chosen measurement function before and during a measurement.
A configuration modified in one of these two ways is updated for both (SET-UP or CONFIG key).
3.1. USING THE LEADS
Specific leads are supplied with the instrument. To use them, you must add test probes or crocodile clips (also supplied with the
instrument).
These accessories have guards. For safety reasons, the user’s hands must always be behind the guard.
The positions the hands must not go beyond are indicated below:
When measuring:
a voltage ≤1000V on mains,
insulation using a test voltage ≤5000V.
For an insulation measurement with a test voltage ≥5000V.
Measurements of voltages ≥1000V on mains must be made using the test probes only, with the user’s hands behind the guard
on the lead.
Remark: The leads with large clips (automobile battery charger type) proposed as accessories cannot be used for mains voltage
measurements because their jaws are not insulated.

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3.2. AC/DC VOLTAGE MEASUREMENT
Turning the switch to any insulation measurement position (U-FIXED, U-VAR, U-RAMP, or U-STEP) sets the instrument to AC/
DC voltage measurement. The voltage between the input terminals is measured at all times and indicated as RMS value on the
display unit: Input Voltage. Switching between AC and DC mode is automatic.
In the case of an AC signal, the instrument measures the frequency. It also measures the residual DC current between the terminals
of the instrument. This measurement is used to evaluate its impact on the insulation measurement about to be made.
The insulation measurements cannot be started if there is an excessively high external voltage (>25V
rms
) on the terminals.
FIXED VOLTAGE
500 V
Input voltage
Frequency
Input current
Date 2011.05.23
230 V AC
50.0 Hz
24.6 nA
Time 10:31
-- V 1000 V
BURN
The blinking symbol then appears next to the measured external voltage value.
The only errors possible in a voltage measurement are:
The frequency is outside the measurement range (see §8.2.1)
The voltage is outside the measurement range (see §8.2.1).
3.3. INSULATION MEASUREMENT
%
The insulation measurement is made on an object that is not live.
This measurement varies greatly with the temperature and the relative humidity. It is therefore
essential to measure them and to record them with the insulation value.
The ambient temperature can be entered in the instrument as a parameter, making it possible
to refer the measured insulation resistance value to a reference temperature (see § 4.1).
The value of the test voltage is generally twice the voltage at which the object to be tested is used, unless a standard stipulates
otherwise.
For example, for a motor that operates on 230V mains, the test will be performed at 500V.
3.3.1. DESCRIPTION OF THE MEASUREMENT PRINCIPLE
The instrument generates a DC test voltage equal to the chosen nominal voltage UNbetween the + and - terminals. More precisely,
the value of this voltage depends on the resistance to be measured (see the curves of §8.2.3). The instrument measures the
voltage and the current between the two terminals and from them deduces R=V/I.
The instrument measures the external voltage present on the terminals. It can make the measurement if the peak voltage is less
than 0.4UN. Beyond this value, it reports an error and does not make the measurement.

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Set the switch to U-FIXED
FIXED VOLTAGE
500 V
Input voltage
Frequency
Input current
Date 2011.05.23
10 V AC
50.0 Hz
24.6 pA
Time 10:31
-- V 1000 V
BURN
The following screen appears.
Use the keys to select the test voltage: 500, 1,000, 2,500, 5,000, 10,000, or 15,000V
dc
,
When the resistance to be measured is low (R<RN=UN/1mA), the voltage generated is lower than the fixed voltage selected. In this
case, it is better to use a variable voltage and adjust UNto the desired value after a first resistance measurement.
3.3.3. WITH A VARIABLE VOLTAGE
MR
U-STEP
U-RAMP
U-VAR.
U-FIXED
OFF
SET-UP
U-FIXED
3.3.2. WITH A FIXED VOLTAGE
Set the switch to U-VAR. The following screen appears.
There are already 3 preset voltages that can be modified in SET-UP (see §5). Use the  keys to select one of them:
Variable Voltage 1: 50V
Variable Voltage 2: 500V
Variable Voltage 3: 2500V
Otherwise, use the keys to go to the voltage value, then use the  keys to adjust the value of the test voltage. The
adjustment is in 10V steps up to 1,000V, then in 100V steps. Keep the keys pressed to speed up the adjustment.
ADJUSTABLE VOLTAGE 1
50 V
Input voltage
Frequency
Input current
Date 2011.05.24
0.1 V AC
0.2 Hz
11.56 pA
Time 15:31
BURN
ADJUSTABLE VOLTAGE
750 V
Input voltage
Frequency
Input current
Date 2011.05.24
0.1 V AC
0.2 Hz
11.56 pA
Time 15:31
BURN
MR
U-STEP
U-RAMP
U-VAR.
U-FIXED
OFF
SET-UP
U-VAR.

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3.3.4. WITH A VOLTAGE RAMP
This test is based on the principle that an ideal insulation produces the same resistance whatever the test voltage applied.
Any negative variation of the insulation resistance therefore means that the insulation is defective: the resistance of defective
insulation decreases as the test voltage increases. This phenomenon is barely observable with low test voltages. At least 2,500V
must therefore be applied.
Since the application of the voltage is gradual, it causes no premature ageing or deterioration of the device tested. Unlike the
increase in steps, the gradual increase of the current means that the capacitive current is constant. A variation of the current
therefore directly represents a variation of the insulation resistance.
Evaluating the result:
a negative slope of the resistance versus test voltage curve exceeding 500ppm/V generally indicates the presence of
mildew or other deterioration.
a larger negative slope, or a sudden drop, indicates the presence of localized physical damage (arcing, perforation of
the insulation, etc.).
Set the switch to U-RAMP. The following screen appears:
RAMP FUNCTION 1
Input voltage
Frequency
Input current
Date 2011.05.24
-0.1 V DC
0.2 Hz
55.7 nA
Time 15:31
Min. 50 V Max. 100 V
BURN
Test Run Time 00:00:30
MR
U-STEP
U-RAMP
U-VAR.
U-FIXED
OFF
SET-UP
U-RAMP
Use the  keys to select a preset test voltage ramp:
Ramp function 1: 50 to 100V
Ramp function 2: 100 to 500V
Ramp function 3: 1000 to 2000V
The voltages at the beginning and end of the ramp can be programmed with the CONFIG key (see §4.3). The duration of the test
is the sum of the three durations specified: the duration of the initial plateau, the duration of the ramp, and the duration of the
final plateau.
3.3.5. WITH A STEPPED VOLTAGE
The stepped voltage has ten plateaus. The duration of each of the voltage plateaus is identical. At the end of each plateau, the
capacitive current is normally zero and only the measurement current remains.
Unlike the ramp test, the step test stresses the insulation and can cause a breakdown. A sudden increase of the current (or a sudden
decrease of the insulation resistance) means that a breakdown point is near. It is then possible to discontinue the measurement
by hand (by pressing the START/STOP button) or automatically (E-BRK or Break at I-Limit type of test; see §4.3.1).
A drop of 25% or more between the insulation resistance of the first plateau and that of the second plateau is a sign of deterioration
of the insulation.

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Set the switch to U-STEP. The following screen appears.
STEP FUNCTION 1
Input voltage
Frequency
Input current
Date 2011.05.24
1 V AC
50.0 Hz
24.6 nA
Time 15:31
BURN
Min. 50 V Max. 500 V
Test Run Time 00:01:40
Use the  keys to choose the preset step type of test:
Step function 1: 50 to 500V
Step function 2: 100 to 1.000V
Step function 3: 500 to 5.000V
The values of the voltages at the beginning and end of a step, the number of steps, and the duration of each step can be
programmed using the CONFIG key (see §4.3).
3.3.6. CONNECTION
Depending on the measurements to be made, there are three ways of connecting the instrument.
In all cases, disconnect the device to be tested from mains.
Low insulation
Connect the red high-voltage lead between earth and the + terminal of the instrument. Connect the black high-voltage lead
between one phase of the motor and the - terminal of the instrument.
MR
U-STEP
U-RAMP
U-VAR.
U-FIXED
OFF
SET-UP
U-STEP
+
-
M

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High insulation
For very high insulation values, connect the small blue high-voltage lead between the earth pick-up of the black lead and the
G terminal of the instrument in order to avoid leakage current and capacitive current effects or to eliminate the influence of the
surface leakage current.
This reduces the influence of the operator’s hands and gives a more stable measurement.
+
-
M
Cable
Connect the red high-voltage lead between the braid and the + terminal of the instrument.
Connect the black high-voltage lead between the core and the - terminal of the instrument.
Connect the blue high-voltage lead between the insulation and the G terminal of the instrument.
G
+
-
Braid
Outer insulation
Insulation
Core
Using the guard eliminates the influence of the surface leakage current.

17

CONFIG

ALARM
If the U-FIXED or U-VAR. test voltages have been selected, it is possible to select a measurement configuration by
pressing the CONFIG key (see §4.3):
Manual Stop
Manual Stop + DD
Timed Run
Timed Run + DD
DAR
PI
Then set the type of test, the maximum current, the current range, the filtering of the measurement, and the value
of the alarm threshold:
Test Type
Maximum Output Current
I-range
Disturbance Level
Alarm

DISPLAY
To activate the alarm, press the ALARM key. An audible beep will sound if the result of the measurement is below
the programmed threshold.
3.3.7. BEFORE THE MEASUREMENT
It is possible to configure the measurement using the CONFIG key
Press the START/STOP button to
start the measurement.
START/STOP

The instrument generates the high voltage. To indicate that the
measurement is in progress, the instrument emits an audible
beep every ten seconds and the START/STOP button lights red.
START/STOP
3.3.8. MEASUREMENT
At the end of a few seconds, the measurement is
displayed in digital form and in analog form on a
bargraph.
If the measurement is unstable, the instrument automatically filters
the signal, but it is possible to apply a digital filter in addition by
pressing the FILTER key (see §4.6).

FILTER
If the test voltage generated is >5000V, the START/STOP button
blinks.
10 100 110 10 10
100 1100 1
kΩMΩGΩTΩ
995 MΩ
528 V 531 nA
Elapsed Time 00:00:23
Set: 500 V
E-BRK

18
configured for a manual stop, once the measurement obtained is stable, press the START/STOP button again to
stop the measurement. In the other cases (programmed duration: Timed Run, Timed Run + DD, DAR, PI, U-RAMP,
or U-STEP), indicated by the symbol, the measurement stops automatically at the end of the test.
START/STOP

At the end of the measurement, the instrument switches back to voltage measurement, but the result of the insulation resistance
measurement remains displayed. To display the voltage, press the DISPLAY key.
995 MΩ
528 V 531 nA
Elapsed Time 00:01:12
DAR (30s/60s)
PI (1.0m/10m)
Capacitance
1.00
---
2.201 nF
E-BRKALARM
Value of the insulation resistance.
Value of the test voltage at the
end of the measurement.
Type of test.
The alarm is active and the
threshold has been crossed.
Duration of the measurement. In
Ancillary results.
Current at the end of the
measurement.
It is possible to view the available digital values by pressing
the DISPLAY key.

DISPLAY
995 MΩ
528 V 531 nA
Elapsed Time 00:01:12
DAR (30s/60s)
PI (1.0m/10m)
Capacitance
1.00
---
---
E-BRK
Set: 500 V
In the case of a step test voltage (10 steps at most) or ramp test voltage (3 steps), the progress of the steps is indicated.
Step 2/10.
Voltage of the second step.
Remaining measurement time.
When the instrument is
5.03 GΩ
209.4 nA
Remaining Time 00:01:25
E-BRK
Step 2/10
10 100 110 10 10
100 1100 1
kΩMΩGΩTΩ
1030 V

19
the case of a ramp or step measurement, the measurement result is displayed as follows:
5.03 GΩ
516 V 98.7 nA
Remaining Time 00:00:00
∆R
∆V
∆R/(R*∆V) (ppm/V)
Capacitance
47.9 MΩ
53.3 V
9
< 1 nF
E-BRK
Test with programmed duration.
Value of the insulation resistance.
Value of the test voltage at the
end of the measurement.
Current at the end of the
measurement.
Duration of the measurement.
Voltage coefficient in ppm/V.
Capacitance of the device
tested.
∆R: difference of insulation
resistance between the final
resistance (highest test voltage)
and the initial resistance (lowest
test voltage).
∆V: difference between the final
and initial test voltages.
Record the measurement and compare it to earlier measurements in order to assess the evolution of its value. Also record the
temperature and the ambient relative humidity.
If, at equivalent temperature and humidity, the insulation resistance has fallen significantly, the insulation is deteriorated and
maintenance must be carried out on the device tested.
The result remains displayed until another measurement is made, the switch is turned, or the measurement configuration is changed.
3.3.9. AFTER THE MEASUREMENT
Once the measurement has been stopped, the instrument discharges the device being tested in a few seconds. For your safety,
therefore, wait a little before disconnecting the leads. Normally, this happens rapidly and the user is unaware of it. But if the load
is highly capacitive, the discharging time is longer. In this case, for as long as the voltage exceeds 25V, the instrument so indicates
on the display unit and by an audible signal.

DISPLAY
The DISPLAY key is used to look up all information available after the measurement. This information depends on
the type of measurement chosen (see §4.4).
995 MΩ
502 V 503 nA
Elapsed Time 00:01:20
DAR (30s/60s)
PI (1.0m/10m)
Capacitance
1.00
---
<1 nF
E-BRK

20

MEM

HELP
Pressing the MEM key records the measurements in memory (see §6.1).
At any time, you can press the HELP key for a reminder of the functions of the keys.
3.4. ERROR INDICATIONS
The commonest error in the case of an insulation measurement is the presence of a voltage on the terminals.
The instrument can make the measurement if the peak value of this voltage is less than 0.4UN.
Above this value, it is necessary to eliminate the voltage and repeat the measurement.
If an external voltage appears on the terminals during the measurement, and its peak value is greater than 1.1UN, the measurement
is broken off and the error is indicated.

GRAPH

TEMP
After a test with programmed duration, pressing the GRAPH key displays the insulation versus time curve (see §4.5).
Pressing the TEMP key opens the temperature menu (see §4.1).