janitza CTB Series User manual

www.janitza.com
Low voltage current transformer
Plug-in current transformer
CTB series
User manual / Mounting instructions
Janitza electronics GmbH
Vor dem Polstück 6
D-35633 Lahnau
Support tel. [phone]
Email: [email protected]
www.janitza.com
Doc. no.: 2.002.189.1.a Date: 05/2023

www.janitza.com
2
CTB series current transformer
Low-voltage current transformer
- Plug-in current transformer -
Doc. no.: 2.002.189.1.a
Date: 05/2023
The German version is the original edition of the documentation
Subject to technical alterations.
The contents of our documentation have been compiled with great care and reflect the current state of the
information available to us. Nonetheless, we wish to point out that updates of this document are not always
possible at the same time as technical refinements are implemented in our products. Please see our website
under www.janitza.com for the current version.
Please see our website under www.janitza.com for the current version.

www.janitza.com
3
CTB series current transformer
TABLE OF CONTENTS
1. Information on the devices and the user manual 4
1. 1 Disclaimer 4
1. 2 Copyright notice 4
1. 3 Technical changes 4
1. 4 About this user manual 4
1. 5 Defective device/disposal 4
2. Safety 5
2. 1 Display of warning notices and safety information 5
2. 2 Hazard levels 5
2. 3 Product safety 5
2. 4 Dangers when handling the device 6
2. 5 Electrically qualified personnel 6
2. 6 Warranty in the event of damage 6
2. 7 Safety information for handling current transformers 7
2. 8 Incoming goods inspection 7
2. 9 Intended use 7
3. Product description 8
3. 1 Principle of operation 8
4. Mounting 9
4. 1 Mounting instructions 9
5. Installation 11
5. 1 Measurement circuit 11
6. Technical data 12
6. 1 General technical data 12
6. 2 Type-specific technical data - Primary rated current and rated power 13
6. 3 Type-specific technical data - Designs 14
6. 4 Dimensional drawings 15

CTB series current transformer www.janitza.com
4
1. Information on the devices and the user manual
1.1 Disclaimer
Compliance with the usage information for the devic-
es is a prerequisite for safe operation and attaining
the stated performance characteristics and product
features.
Janitza electronics GmbH assumes no liability for
bodily injury, material damage or financial losses
which result from disregard of the usage information.
Ensure that the usage information for the products is
legible and accessible.
1.2 Copyright notice
© 2019 - Janitza electronics GmbH - Lahnau. All
rights reserved.
Any reproduction, processing, distribution or other
use of this usage information, in whole or in part, is
prohibited.
All trademarks and the rights arising from them are
the property of the respective owners of these rights.
1.3 Technical changes
· Make sure that your device matches the user man-
ual.
· This user manual applies to the low-voltage current
transformers (plug-in current transformers) of the
CTB series.
· First make sure you have read and understood the
usage information accompanying the product.
· Keep the usage information associated with the
product available for the entire service life and pass
it on to any possible subsequent users.
· Find out about device revisions and the associated
modifications of the usage information associated
with your product at www.janitza.com.
1.4 About this user manual
If you have questions, suggestions or ideas for im-
provement of the user manual, please let us know via
email at: [email protected].
1.5 Defective device/disposal
Before sending defective devices, modules or
components back to the manufacturer for testing:
· Contact the manufacturer's Support department.
· Send devices, modules or components complete
with all accessories.
· When doing so, please bear the terms for transpor-
tation in mind.
INFORMATION
· Before assembly and commissioning, check the
device for possible transport damage.
· Do not put defective devices into service!
· Please return defective or damaged devices, mod-
ules or components to Janitza electronics GmbH in
accordance with the shipping instructions for air or
road freight (complete with accessories).
Do not attempt to open or repair the device (the
module, the component) on your own because oth-
erwise all warranty claims become invalid!
For the disposal of the device (the module, the
component), please observe national regulations!
Dispose of individual parts, as applicable, depending
on their composition and existing country-specific
regulations, e.g. as
· Electronic waste,
· Batteries and rechargeable batteries.
· Plastics.
· Metals.
Engage a certified disposal company to handle
scrapping as needed.
INFORMATION
This user manual describes the low-voltage current
transformers (plug-in current transformers) of the
CTB series and provides information on the operation
of the devices.
Observe any additional usage information and, in par-
ticular, the safety information in this user manual.

www.janitza.com
5
CTB series current transformer
2. Safety
The chapter on Safety contains information which
must be observed to ensure your personal safety
and avoid material damage.
2.1 Display of warning notices and safety infor-
mation
The warning notices shown below
· are found throughout the usage information.
· can possibly be found on the devices themselves.
· indicate potential risks and hazards.
· underscore aspects of the information provided that
clarifies or simplifies procedures.
This additional symbol on the device (module/com-
ponent) itself indicates an electrical hazard that can
lead to severe injury or death.
This general warning symbol draws attention to a
possible risk of injury. Be certain to observe all of the
information listed under this symbol in order to avoid
possible injury or even death.
2.2 Hazard levels
Warning and safety information is marked by a
warning symbol, and the hazard levels are shown as
follows, depending on the degree of hazard:
DANGER
Warns of an imminent danger which, if not avoided,
results in serious or fatal injury.
WARNING
Warns of a potentially hazardous situation which, if
not avoided, could result in serious injury or death.
CAUTION
Warns of an immediately hazardous situation which,
if not avoided, can result in minor or moderate injury.
ATTENTION
Warns of an immediately hazardous situation which,
if not avoided, can result in material or environmental
damage.
INFORMATION
Indicates procedures in which there is no hazard of
personal injury or material damage.
2.3 Product safety
The devices reflect current engineering practice and
accepted safety standards, but hazards can arise
nonetheless.
Observe the safety regulations and warning notices.
If notices are disregarded, this can lead to personal
injury and/or damage to the product.
Every type of tampering with or use of the devices,
· which goes beyond the mechanical, electrical or
other operating limits can lead to personal injury
and/or damage to the product;
· constitutes “misuse” and/or “negligence” under the
product’s warranty and thus voids the warranty for
any possible resulting damage.
Read and understand the user manual before as-
sembling, installing, operating, maintaining or using
the devices.
· Only operate the devices when in perfect condition
and in compliance with this user manual and the
usage information that is included.
· Send defective devices back to the manufacturer in
compliance with proper transport conditions.
· Retain the user manual throughout the service life
of your product and keep it at hand for consulta-
tion.
When using the device, component or module, also
observe the legal and safety regulations for your sys-
tem that are applicable for the respective use case.

CTB series current transformer www.janitza.com
6
WARNING
Risk of injury due to electrical current and voltage!
Severe bodily injury or death can result! Therefore
please abide by the following:
· Do not touch bare, stripped wires or device inputs
that are dangerous to touch on the devices, com-
ponents and modules.
· Switch off your installation before commencing
work! Secure it against being switched on! Check
to be sure it is de-energized! Ground and short
circuit! Cover or block off adjacent live parts!
· During operation and troubleshooting, check the
environment for dangerous voltages and switch
these off if necessary!
· Wear protective clothing and protective equipment
in accordance with applicable guidelines when
working on electrical systems!
· Before making connections, ground the device /
component / module by means of the ground wire
connection, if present!
· Do not touching bare or stripped leads that are
energized! Equip stranded conductors with wire
ferrules!
· Hazardous voltages can be present in all circuitry
parts that are connected to the power supply.
· Protect wires, cables and devices with a suitable
line circuit breaker/fuse!
· Never switch off, remove or tamper with safety
devices!
· There can still be hazardous voltages present in
the device or in the component even after it has
been disconnected from the supply voltage. Check
to be sure it is de-energized!
· Do not operate equipment with current transformer
circuits when open.
· Only connect screw terminals with the same num-
ber of poles and design!
· Do not exceed the limit values specified in the user
manual and on the rating plate! This must also be
observed during testing and commissioning.
· Observe the safety and warning notices in the
usage information associated with the devices or
components!
2.4 Dangers when handling the device
When operating electric devices, components or
modules, it is unavoidable for certain parts of these
devices to conduct hazardous voltage. Consequent-
ly, severe bodily injury or material damage can occur
if they are not handled properly.
When handling the devices, always observe the
following:
· do not exceed the limit values specified in the user
manual and on the rating plate! This must also be
observed during testing and commissioning!
· Take note of the safety and warning notices in all
usage information that belongs to the device, com-
ponents or modules!
· Applicable laws, standards and regulations!
· The state of the art and current engineering prac-
tice at the point in time of installation.
2.5 Electrically qualified personnel
To avoid bodily injury and material damage, only
electrically qualified personnel are permitted to work
on the devices and their components, modules,
assemblies, systems and current circuits who have
knowledge of:
· The national and international accident prevention
regulations.
· Safety technology standards.
· Installation, commissioning, operation, disconnec-
tion, grounding and marking of electrical equip-
ment.
· The requirements concerning personal protective
equipment.
Electrically qualified persons within the scope of the
technical safety information of all usage information
associated with the device and its components are
persons who can furnish proof of qualification as an
electrically skilled person.
2.6 Warranty in the event of damage
Any unauthorized tampering with or use of the
device, component or module constitutes “misuse”
and/or “negligence” under the product’s warranty
and thus voids the warranty for any possible re-
sulting damage. In this regard, please take note of
section „6.3 Type-specific technical data - Designs“
on page 14.

www.janitza.com
7
CTB series current transformer
WARNING
Warning of unauthorized tampering or improper
use of the device!
Opening, dismantling or unauthorized manipulation of
the device which goes beyond the mechanical, elec-
trical or other operating limits indicated can lead to
material damage or injury, up to and including death.
· Only electrically qualified personnel are permitted
to work on the devices, components, assemblies,
systems and current circuits.
· Always use your device only in the manner de-
scribed in the associated usage information.
· If there is discernible damage, send the device
back to the manufacturer!
2.8 Incoming goods inspection
The prerequisites for trouble-free and safe operation
of the devices include proper transport, storage,
setup andassembly, as well as proper operation
andmaintenance.
Exercise due caution when unpacking and packing
the device, do not use force and only use suitable
tools. Check the following:
· Visually inspect the devices for flawless mechanical
condition.
· Your delivered devices for completeness before you
start with assembly and installation.
If it must be assumed that safe operation of your
device is not possible:
1. Switch off the power to your system (your
device)!
2. Secure it against being switched back on!
3. Check to be sure it is de-energized!
4. Ground and short circuit the system (device)!
5. Cover or block off adjacent live parts!
Safe operation isimpossible, if the device:
· has visible damage,
· no longer functions despite an intact power supply,
· was subjected to extended periods ofunfavorable
conditions (e.g. storage outside of the permissible
climate thresholds without adjustment to the room
climate, condensation, etc.) or transport stress
(e.g. falling from anelevated position, even without
visible external damage, etc.).
2.9 Intended use
The device:
· Is only for use in the industrial sector.
· Is intended for use in dry, electrical operating rooms
and closed housings, such as switchboard cabinets
and small distribution boards.
The device is not for installation
· In vehicles! Use of the device in non-stationary
equipment constitutes an exceptional environmen-
tal condition and is only permissible by special
agreement.
· In environments with harmful oils, acids, gases,
vapors, dusts, radiation, etc.
· In potentially explosive environments.
2.7 Safety information for handling current
transformers
WARNING
Risk of injury due to large currents and high elec-
trical voltage on the current transformers!
Current transformers operated while open on the
secondary side (high voltage peaks pose a hazard
when touched) can result in severe bodily injury or
death.
· Avoid operating the current transformers while
open; short circuit the unloaded transformers!
· Before interrupting the current supply, short circuit
the secondary connections of the current trans-
formers. Switch any test switches that auto-
matically short circuit the secondary lines of the
current transformers to the “Test” status (Check
the test switch/short circuiting connection before-
hand)!
· Only use current transformers with basic insulation
to IEC61010-1:2010!
· Caution, even current transformers rated as safe
for open operation can pose a hazard when
touched during operation while open!
· Make sure that screw terminals for the current
transformer connection on the device are ade-
quately tightened!
· Comply with the information and provisions in the
documentation of your current transformers!
CAUTION
Risk of injury or damage to the meter due to high
measurement currents at the connections of the
current transformers!
High measurement currents can cause temperatures
of up to 80°C (176°F) on the connections of the
current transformers
· Use wiring that is designed for an operating tem-
perature of at least 80°C (176°F)!
· The current transformers can be hot even after the
power supply has been switched off. Allow the
connections of the current transformers and the
connecting cables to cool down before touching
them!

CTB series current transformer www.janitza.com
8
3. Product description
3.1 Principle of operation
CTB series current transformers
· are inductive, single-conductor current transformers
that operate according to the transformer principle.
· are used to adapt a primary measured variable to
the nominal input variables of connected measure-
ment devices.
· are, due to the measuring principle, only suitable for
use in AC networks.
· are maintenance-free.

www.janitza.com
9
CTB series current transformer
4. Mounting
4.1 Mounting instructions
1. Use of the secondary terminals (CAGE CLAMP®)
2. Mounting the fastening screws
3. Mounting on copper rail and round conductor 4. Mounting with snap-on mounting
5. Mounting on 35 mm DIN mounting rail with snap-on mounting (CTB 31.35 and CTB 41.35 only)

www.janitza.com
10
CTB series current transformer
6. Mounting on a mounting plate
CTB 31.35 CTB 41.35 CTB 51.35 CTB 61.35 CTB 81.35 CTB 101.35
Dimension "A"
[mm / in] 40 / 1.57 40 / 1.57 65 / 2.56 65 / 2.56 95 / 3.74 95 / 3.74
Tab. Dimensions for mounting the device on a mounting plate.
Dimensions in mm
[2.09in]
[0.26in]

www.janitza.com
11
CTB series current transformer
5. Installation
· Ensure there is a safe working environment during
assembly, maintenance and installation work. Dis-
connect the power supply of the primary conductor
and secure it against unintentional reconnection.
· Install the current transformer on the primary con-
ductor.
· To do so, guide the primary conductor (Cu rail or
round conductor) through the window opening of
the current transformer housing. The window open-
ing is marked with "K-P1" or "L-P2".
· Mount the device either directly on the primary con-
ductor or on a mounting plate. Use the fasteners
included in the scope of delivery for this purpose.
Fastening
- can be carried out directly on the primary con-
ductor by screwing the fastening screws into
the screw bosses located on the transformer
housing or using the optionally available snap-
on mounting.
- can be carried out on the mounting plate using
the foot brackets.
· Current transformers of types CTB 31.35 and CTB
41.35 can also be mounted on a 35 mm (1.38 in)
DIN mounting rail with a snap-on mounting avail-
able as an accessory.
· Connect the secondary terminals observing the
markings "k-S1" and "l-S2".
5.1 Measurement circuit

www.janitza.com
12
CTB series current transformer
6. Technical data
ATTENTION
In addition to the following technical data, pay particu-
lar attention to the information on the rating plate of
your device!
6.1 General technical data
Input
Primary rated current Ipr
(type-dependent)
see chapter 6.2 on page
13
Thermal
rated continuous current Icth
1.2 x Ipr
(> 2000 A: 1.0 x Ipr)
Thermal
rated short-time current Ith
60 x Ipr / 1s
(max. 100kA)
Rated surge current Idyn 2.5 x Ith
Rated frequency fR50 ... 60 Hz
Tab. Technical data - Input
Output
Secondary rated current Isr 5A
Accuracy class 1
Rated power Sr
(type-dependent)
see chapter 6.2 on page
13
Overcurrent limiting factor FSFS5 or FS10
Tab. Technical data - Output
Operating conditions
Ambient temperature -5 … +50°C
(23... 122°F)
Storage temperature -25 … +70°C
(-13... 158°F)
Relative humidity (non-condens-
ing) 5 … 85%
Operating elevation Up to 1000m
(1093.61yd)
Tab. Technical data - Operating conditions
Isolation properties
Rated isolation level Um
in accordance with IEC61010-1
under the following conditions:
- Overvoltage category III
- Pollution degree 2
- Heterogeneous electrical field
1.2/6/-kV
Surge voltage strength in
accordance with
DIN EN 61439-1:2012-06
12 kV (1.2/50 μs)
Insulation class E
Tab. Technical data - Isolation properties
Safety
Protection level IP20
Housing material PC
UL housing classification of
these types UL94-V0
Overcurrent limiting factor FSFS5 or FS10
Tab. Technical data - Safety
Connection
Primary conductor feedthrough see chapter 6.3 on page
14
Connection technology, second-
ary CAGE CLAMP®
Connection cross section, sec-
ondary
2.5 - 4 mm² /
AWG 14-12
Strip length 9 - 10mm
(0.35 - 0.39in)
Tab. Technical data - Connection
The latest edition of the aforementioned documents,
including all amendments, applies.
Standards complied with
· IEC 61869-1
· IEC 61869-2
· IEC 61010-1
Tab. Technical data - Standards complied with

www.janitza.com
13
CTB series current transformer
6.2 Type-specific technical data - Primary rated current and rated power
Current transformer type Primary rated current [A] Rated power [VA]
CTB 31.35 100 2.5
CTB 31.35 150 2.5
CTB 31.35 200 2.5
CTB 31.35 250 5
CTB 31.35 300 5
CTB 31.35 400 5
CTB 31.35 500 5
CTB 41.35 800 5
CTB 41.35 1000 5
CTB 51.35 1250 5
CTB 61.35 1500 5
CTB 81.35 1500 10
CTB 81.35 1600 10
CTB 81.35 2000 10
CTB 101.35 2500 10
Tab. Type-specific technical data - Primary rated current and rated power

www.janitza.com
14
CTB series current transformer
6.3 Type-specific technical data - Designs
Overall width
Overall height
Overall
depth
Type
CTB 31.35
Type
CTB 41.35
Type
CTB 51.35
Type
CTB 61.35
Type
CTB 81.35
Type
CTB 101.35
Primary conductor feedthrough
Rail 1 [mm / in] 30 x 10 /
1.18x0.39 40 x 10/ 1.57x0.39 50 x 12/ 1.97x0.47 63 x 10/ 2.48x0.39 80 x 10/ 3.15x0.39 100 x 10/ 3.94x0.39
Rail 2 [mm / in] 25 x 12/
0.98x0.47 30 x15/ 1.18x0.59 40 x 30/ 1.57x1.18 50 x 30/ 1.97x1.18 60 x 30/ 2.36x1.18 80 x 30/ 3.15x1.18
Rail 3 [mm / in] 20 x 20/
0.79 x 0.79 --- --- --- --- ---
Round conductor
[mm / in] 25.7/1.01 31.8/1.25 43.7/1.72 43.7/1.72 54.7/2.15 70/2.76
Dimensions
Overall width [mm
/ in] 60 / 2.36 70 / 2.76 85 / 3.35 95 / 3.74 120 / 4.72 130 / 5.12
Overall height [mm
/ in] 80.5 / 3.17 91.15 / 3.59 105.25 / 4.14 114.86 / 4.52 134.66 / 5.3 147.49 / 5.81
Overall depth
[mm / in] 52 / 2.05 52 / 2.05 52 / 2.05 52 / 2.05 52 / 2.05 52 / 2.05
Weight
Weight [g / lb] 230 / 0.51 300 / 0.66 350 / 0.77 350 / 0.77 380 / 0.84 400 / 0.88
Tab. Type-specific technical data

www.janitza.com
15
CTB series current transformer
6.4 Dimensional drawings
INFORMATION
The dimensional drawings are not to scale! All
dimensions in mm!
31,80
70
40,30 30,30 15,80
10,30
10,30
15,80
30,30
37
91,15
61
10,30
30,30
120
54,70
60,20
80,20
134,66
85
43,70
43,25
30,30
12,30
40,30
105,25
66
70
130
30,30
10,30
80,50
100,50
147,49
95
48,50
50,20
63,20
30,30
10,30
43,70
114,86
68
33
35
37
52
52
67
35
52
37 35
52
37
68
53
52
37
35
37
35
52
52
67
25,70
60
31,50
30,30 25,30 20,30
12,30 10,30
30,30
25,30
20,30
12,30
10,30
80,9
52
37
35
33
68
52
67
31,80
70
40,30 30,30 15,80
10,30
10,30
15,80
30,30
37
91,15
61
10,30
30,30
120
54,70
60,20
80,20
134,66
85
43,70
43,25
30,30
12,30
40,30
105,25
66
70
130
30,30
10,30
80,50
100,50
147,49
95
48,50
50,20
63,20
30,30
10,30
43,70
114,86
68
33
35
37
52
52
67
35
52
37 35
52
37
68
53
52
37
35
37
35
52
52
67
25,70
60
31,50
30,30 25,30 20,30
12,30 10,30
30,30
25,30
20,30
12,30
10,30
80,9
52
37
35
33
68
52
67
6.4.1 CTB 31.35
6.4.2 CTB 41.35

CTB series current transformer www.janitza.com
16
31,80
70
40,30 30,30 15,80
10,30
10,30
15,80
30,30
37
91,15
61
10,30
30,30
120
54,70
60,20
80,20
134,66
85
43,70
43,25
30,30
12,30
40,30
105,25
66
70
130
30,30
10,30
80,50
100,50
147,49
95
48,50
50,20
63,20
30,30
10,30
43,70
114,86
68
33
35
37
52
52
67
35
52
37 35
52
37
68
53
52
37
35
37
35
52
52
67
25,70
60
31,50
30,30 25,30 20,30
12,30 10,30
30,30
25,30
20,30
12,30
10,30
80,9
52
37
35
33
68
52
67
31,80
70
40,30 30,30 15,80
10,30
10,30
15,80
30,30
37
91,15
61
10,30
30,30
120
54,70
60,20
80,20
134,66
85
43,70
43,25
30,30
12,30
40,30
105,25
66
70
130
30,30
10,30
80,50
100,50
147,49
95
48,50
50,20
63,20
30,30
10,30
43,70
114,86
68
33
35
37
52
52
67
35
52
37 35
52
37
68
53
52
37
35
37
35
52
52
67
25,70
60
31,50
30,30 25,30 20,30
12,30 10,30
30,30
25,30
20,30
12,30
10,30
80,9
52
37
35
33
68
52
67
6.4.3 CTB 51.35
6.4.4 CTB 61.35

www.janitza.com
17
CTB series current transformer
31,80
70
40,30 30,30 15,80
10,30
10,30
15,80
30,30
37
91,15
61
10,30
30,30
120
54,70
60,20
80,20
134,66
85
43,70
43,25
30,30
12,30
40,30
105,25
66
70
130
30,30
10,30
80,50
100,50
147,49
95
48,50
50,20
63,20
30,30
10,30
43,70
114,86
68
33
35
37
52
52
67
35
52
37
35
52
37
68
53
52
37
35
37
35
52
52
67
25,70
60
31,50
30,30 25,30 20,30
12,30 10,30
30,30
25,30
20,30
12,30
10,30
80,9
52
37
35
33
68
52
67
31,80
70
40,30 30,30 15,80
10,30
10,30
15,80
30,30
37
91,15
61
10,30
30,30
120
54,70
60,20
80,20
134,66
85
43,70
43,25
30,30
12,30
40,30
105,25
66
70
130
30,30
10,30
80,50
100,50
147,49
95
48,50
50,20
63,20
30,30
10,30
43,70
114,86
68
33
35
37
52
52
67
35
52
37 35
52
37
68
53
52
37
35
37
35
52
52
67
25,70
60
31,50
30,30 25,30 20,30
12,30 10,30
30,30
25,30
20,30
12,30
10,30
80,9
52
37
35
33
68
52
67
6.4.5 CTB 81.35
6.4.6 CTB 101.35

Janitza electronics GmbH
Vor dem Polstück 6
D-35633 Lahnau
Support tel. [phone]
Email: [email protected]
www.janitza.com