IEC 61812-1:2011

Time relays for industrial and residential use - Part 1: Requirements and tests

IEC 61812-1:2011 applies to time relays for industrial applications (e.g. control, automation, signal and industrial equipment). It also applies to time relays for automatic electrical controls for use in, on, or in association with equipment for residential and similar use. This edition includes the following significant technical changes with respect to the previous edition:
- addition of terms and definitions more commonly used by industry;
- addition of timing charts to help explain terms and definitions involving a sequence of events;
- addition of provisions for residential use.

Relais à temps spécifié pour applications industrielles et résidentielles - Partie 1: Exigences et essais

La CEI 61812-1:2011 s'applique aux relais à temps spécifié utilisés dans les applications industrielles (par exemple: équipements industriels de commande, d'automatisme et de signalisation). Elle s'applique également aux relais à temps spécifié de commandes électriques automatiques utilisées comme éléments constitutifs, auxiliaires ou associés aux équipements utilisés dans des applications résidentielles et analogues. Cette édition comprend les modifications techniques significatives suivantes par rapport à l'édition précédente:
- ajout des termes et définitions les plus couramment utilisés dans le secteur industriel;
- ajout de chronogrammes permettant de mieux expliquer les termes et définitions impliquant une séquence d'événements;
- ajout de dispositions relatives à des applications résidentielles.

General Information

• Status: Published
• Publication Date: 24-May-2011
• ICS: 29.120.70 - Relays
• Technical Committee: TC 94 - Electrical relays
• Drafting Committee: MT 4 - TC 94/MT 4
• Current Stage: DELPUB - Deleted Publication
• Start Date: 08-Jun-2023
• Completion Date: 31-Jan-2020

Relations

• Revised: IEC 61812-1:2023 - Time relays and coupling relays for industrial and residential use - Part 1: Requirements and tests
• Effective Date: 05-Sep-2023
• Revises: IEC 61812-1:1996 - Specified time relays for industrial use - Part 1: Requirements and tests
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61812-1 ®
Edition 2.0 2011-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Time relays for industrial and residential use –
Part 1: Requirements and tests

Relais à temps spécifié pour applications industrielles et résidentielles –
Partie 1: Exigences et essais
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IEC 61812-1 ®
Edition 2.0 2011-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Time relays for industrial and residential use –
Part 1: Requirements and tests

Relais à temps spécifié pour applications industrielles et résidentielles –
Partie 1: Exigences et essais
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX X
ICS 29.120.70 ISBN 978-2-88912-488-6

– 2 – 61812-1  IEC:2011
CONTENTS
FOREWORD . 5
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 9
3.1 Terms and definitions related to general terms . 9
3.2 Terms and definitions of relay types . 11
4 Influence quantities . 17
5 Rated values . 18
5.1 General . 18
5.2 Input voltage and frequency . 18
5.3 Release voltage . 19
5.4 Power consumption . 19
5.5 Output circuit . 19
5.5.1 Electromechanical output circuit . 19
5.5.2 Mechanical endurance . 19
5.5.3 Solid state output circuit . 19
5.5.4 Endurance and operating frequency . 20
5.5.5 Conditional short circuit current . 20
5.6 Ambient temperature . 20
5.7 Transport and storage temperature . 20
5.8 Humidity . 20
5.9 Pollution degree . 21
5.10 Altitude . 21
5.11 Timing circuit function . 21
5.11.1 General . 21
5.11.2 Setting accuracy . 21
5.11.3 Repeatability . 21
5.11.4 Recovery time and minimum control impulse . 21
6 Provisions for testing . 22
7 Documentation and marking . 22
7.1 Data . 22
7.2 Marking . 24
8 Heating . 25
8.1 General . 25
8.2 Test conditions . 25
8.3 Heating of terminals . 25
8.3.1 General . 25
8.3.2 Heating of screw terminals and screwless terminals . 25
8.3.3 Heating of quick-connect terminations . 26
8.3.4 Heating of sockets . 26
8.3.5 Heating of alternative termination types . 27
8.4 Heating of accessible parts . 27
8.5 Heating of insulating materials . 27
9 Basic operating function . 27
9.1 General . 27
9.2 Operate . 27

61812-1  IEC:2011 – 3 –
9.3 Release . 28
9.4 Time function . 28
9.4.1 Functional test at reference values of input quantities . 28
9.4.2 Influencing effects of voltage and temperature . 28
10 Insulation . 28
10.1 General . 28
10.2 Preconditioning . 29
10.3 Dielectric strength . 29
10.3.1 General . 29
10.3.2 Impulse withstand test . 29
10.3.3 Dielectric a.c. power frequency voltage test . 30
10.4 Protection against direct contact . 31
11 Electrical endurance . 31
11.1 General . 31
11.2 Resistive loads, inductive loads, and special loads . 32
11.3 Low energy loads . 32
12 Conditional short-circuit current . 32
12.1 General . 32
12.2 Test procedure . 32
12.3 Test circuit electromechanical output circuit . 32
12.4 Test circuit solid state output circuit . 33
12.5 Condition of switching element after test . 34
13 Clearances and creepage distances . 34
13.1 General . 34
13.2 Creepage distances. 35
13.3 Clearances . 36
13.4 Measurement of creepage distances and clearances . 37
14 Mechanical strength . 37
14.1 General . 37
14.2 Mechanical strength of terminals and current-carrying parts . 38
14.2.1 General . 38
14.2.2 Mechanical strength of screw terminals and screwless terminals . 38
14.2.3 Mechanical strength of flat quick-connect terminations . 38
14.2.4 Mechanical strength of sockets . 38
14.2.5 Mechanical strength of alternative termination types . 38
15 Heat and fire resistance. 38
16 Vibration and shock . 39
16.1 Vibration. 39
16.2 Shock . 39
17 Electromagnetic compatibility (EMC) . 40
17.1 General . 40
17.2 EMC immunity . 40
17.3 EMC radiated and conducted emission . 42
Annex A (informative) Ball pressure test . 44
Bibliography . 45

Figure 1 – Definition of ports . 11

– 4 – 61812-1  IEC:2011
Figure 2 – Definition of symbols . 11
Figure 3 – Power on-delay relay . 12
Figure 4 – Power off-delay relay . 12
Figure 5 – Off-delay relay with control signal . 12
Figure 6 – On- and off-delay relay with control signal . 13
Figure 7 – Flasher relay . 13
Figure 8 – Star-delta relay . 14
Figure 9 – Summation time relay. 14
Figure 10 – Pulse delayed relay . 15
Figure 11 – Pulse delayed relay with control signal . 15
Figure 12 – Interval relay . 15
Figure 13 – Interval relay with control signal . 16
Figure 14 – Retriggerable interval relay with control signal on . 16
Figure 15 – Retriggerable interval relay with control signal off . 17
Figure 16 – Maintained time relay . 17
Figure 17 – Test circuit electromechanical output, conditional short-circuit current . 33
Figure 18 – Test circuit solid state output, conditional short-circuit current . 34

Table 1 – Influence quantities and reference values . 17
Table 2 – Preferred values of endurance . 20
Table 3 – Preferred values of maximum permissible operating frequency. 20
Table 4 – Recommended final values of the setting range . 21
Table 5 – Type testing . 22
Table 6 – Required relay information . 23
Table 7 – Areas and lengths of conductors dependent on the current carried by the
terminal . 26
Table 8 – Temperature rise limits of accessible parts . 27
Table 9 – Changing of influencing quantities . 28
Table 10 – Impulse test for basic insulation . 30
Table 11 – Dielectric test voltage for devices suitable for use in single-phase three or
two-wire a.c. and d.c. systems . 30
Table 12 – Dielectric test voltage for devices suitable for use in three-phase four or
three-wire a.c. systems . 31
Table 13 – Minimum creepage distances for basic insulation . 36
Table 14 – Minimum clearances for basic insulation . 37
Table 15 – Minimum clearances in controlled overvoltage conditions for internal
circuits . 37
Table 16 – Environmental conditions influencing EMC . 40
Table 17 – Immunity tests for industrial environments . 41
Table 18 – Immunity tests for residential, commercial and light-industrial environments . 42

61812-1  IEC:2011 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
_____________
TIME RELAYS FOR INDUSTRIAL AND RESIDENTIAL USE –

Part 1: Requirements and tests

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
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6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
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expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61812-1 has been prepared by IEC technical committee 94: All-or-
nothing electrical relays.
This second edition cancels and replaces the first edition published in 1996. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
– update of references;
– addition of terms and definitions more commonly used by industry;
– addition of timing charts to help explain terms and definitions involving a sequence of
events;
– renumbering of clauses to bring them into a more logical order;
– addition of provisions for residential use.

– 6 – 61812-1  IEC:2011
The text of this standard is based on the following documents:
FDIS Report on voting
94/324/FDIS 94/333/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of the IEC 61812 series can be found, under the general title Time relays for
industrial and residential use, on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
61812-1  IEC:2011 – 7 –
TIME RELAYS FOR INDUSTRIAL AND RESIDENTIAL USE –

Part 1: Requirements and tests

1 Scope
This part of the IEC 61812 applies to time relays for industrial applications (e.g. control,
automation, signal and industrial equipment).
It also applies to time relays for automatic electrical controls for use in, on, or in association
with equipment for residential and similar use.
The term “relay” as used in this standard comprises all types of relays with specified time
functions, other than measuring relays.
NOTE Depending on the field of application of these relays (for example automatic electrical controls for
household and similar use, switches for household and similar fixed electrical installations), further standards may
be applicable, for example IEC 60730-2-7 or IEC 60669-2-3.
2 Normative references
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
IEC 60050-444:2002, International Electrotechnical Vocabulary – Part 444: Elementary relays
IEC 60050-445:2010, International Electrotechnical Vocabulary – Part 445: Time relays
IEC 60068 (all parts), Environmental testing
IEC 60068-2-2:2007, Environmental testing – Part 2-2: Tests – Test B: Dry heat
IEC 60068-2-6:2007, Environmental testing – Part 2-6: Tests – Test Fc: Vibration (sinusoidal)
IEC 60068-2-27:2008, Environmental testing – Part 2-27: Tests – Test Ea and guidance:
Shock
IEC 60085:2007, Electrical insulation – Thermal evaluation and designation
IEC 60112:2003, Method for the determination of the proof and the comparative tracking
indices of solid insulating materials
IEC 60529:1989, Degrees of protection provided by enclosures (IP Code)
IEC 60664 (all parts), Insulation coordination for equipment within low-voltage systems
IEC 60664-1:2007, Insulation coordination for equipment within low-voltage systems – Part 1:
Principles, requirements and tests
IEC 60664-3:2003, Insulation coordination for equipment within low-voltage systems – Part 3:
Use of coating, potting or moulding for protection against pollution

– 8 – 61812-1  IEC:2011
IEC 60664-5:2007, Insulation coordination for equipment within low-voltage systems – Part 5:
Comprehensive method for determining clearances and creepage distances equal to or less
than 2 mm
IEC 60695-2-11:2000, Fire hazard testing – Part 2-11: Glowing/hot-wire based test methods –
Glow-wire flammability test method for end-products
IEC 60695-10-2:2003, Fire hazard testing – Part 10-2: Abnormal heat – Ball pressure test
IEC 60947-5-4:2002, Low-voltage switchgear and controlgear – Part 5-4: Control circuit
devices and switching elements – Method of assessing the performance of low-energy
contacts – Special tests
IEC 60999-1:1999, Connecting devices – Electrical copper conductors – Safety requirements
for screw-type and screwless-type clamping units – Part 1: General requirements and
2 2
particular requirements for clamping units for conductors from 0,2 mm up to 35 mm
(included)
IEC 61000-4-2:2008, Electromagnetic compatibility (EMC) – Part 4-2: Testing and
measurement techniques – Electrostatic discharge immunity test
IEC 61000-4-3:2006, Electromagnetic compatibility (EMC) – Part 4-3: Testing and
measurement techniques – Radiated, radio-frequency, electromagnetic field immunity test
IEC 61000-4-4:2004, Electromagnetic compatibility (EMC) – Part 4-4: Testing and
measurement techniques – Electrical fast transient/burst immunity test
IEC 61000-4-5:2005, Electromagnetic compatibility (EMC) – Part 4-5: Testing and
measurement techniques – Surge immunity test
IEC 61000-4-6:2008, Electromagnetic compatibility (EMC) – Part 4-6: Testing and
measurement techniques – Immunity to conducted disturbances, induced by radio-frequency
fields
IEC 61000-4-8:2009, Electromagnetic compatibility (EMC) – Part 4-8: Testing and
measurement techniques – Power frequency magnetic field immunity test
IEC 61000-4-11:2004, Electromagnetic compatibility (EMC) – Part 4-11: Testing and
measurement techniques – Voltage dips, short interruptions and voltage variations immunity
tests
IEC 61210:2010, Connecting devices – Flat quick-connect terminations for electrical copper
conductors – Safety requirements
IEC 61810-1:2008, Electromechanical elementary relays – Part 1: General requirements
IEC 61984:2008, Connectors – Safety requirements and tests
IEC 62314:2006, Solid-state relays
CISPR 11:2009, Industrial, scientific and medical equipment – Radio-frequency disturbance
characteristics – Limits and methods of measurement
Amendment 1 (2010)
CISPR 22:2008, Information technology equipment – Radio disturbance characteristics –
Limits and methods of measurement

61812-1  IEC:2011 – 9 –
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-444 and
IEC 60050-445, as well as the following apply.
NOTE Terms having the same or nearly the same meaning are printed in boldface on separate lines and can be
used as an alternative.
3.1 Terms and definitions related to general terms
3.1.1
time relay
specified-time relay
all-or-nothing relay (IEC 60050-444:2002, 444-01-02) with one or more time functions
[IEC 60050-445:2010, 445-01-01 modified]
3.1.2
specified time
specified characteristic of a time relay at given type of function, e.g. operate time, release
time, pulse on time, interval time
[IEC 60050-445:2010, 445-05-01]
3.1.3
setting accuracy
difference between the measured value of the specified time and the reference value set on
the scale
NOTE For analogue setting this value relates to the maximum setting value.
[IEC 60050-445:2010, 445-06-07]
3.1.4
effect of influence (on specified time)
degree with which the influence quantity within its nominal range has an effect on the
specified time
[IEC 60050-445:2010, 445-06-02]
3.1.5
recovery time
minimum time interval for which the power supply is removed or control signal is applied or
removed before the specified function can be performed again
[IEC 60050-445:2010, 445-05-04]
3.1.6
minimum control impulse time
shortest duration of the power supply or control signal to fulfil the specified function
[IEC 60050-445:2010, 445-05-02]
3.1.7
repeatability
difference between the upper and lower limits of the specified confidence range determined
from several time measurements of a time relay under identical conditions
NOTE Preferably the repeatability is indicated as a percentage of the mean value of all measured values.
[IEC 60050-445:2010, 445-06-08]

– 10 – 61812-1  IEC:2011
3.1.8
power supply
energizing quantity
electrical quantity (e.g. electric current, voltage) which has to be applied or removed from the
input circuit of the time relay in order to enable it to fulfil its purpose
[IEC 60050-445:2010, 445-03-01]
3.1.9
input voltage
input current
electrical quantity that can be applied (or removed) to the power supply and to the control
signal
3.1.10
control signal
trigger signal (deprecated)
input signal which has to be applied or removed in addition to the power supply in order to
ensure a function of the time relay
NOTE The control signal is provided by a separate device designed to close or open an electrical circuit.
[IEC 60050-445:2010, 445-02-05]
3.1.11
conditional short-circuit current of an output circuit
prospective electric current that a contact circuit, protected by a specified short-circuit
protective device, can satisfactorily withstand for the total breaking time of that protective
device under specified conditions of use and behaviour
[IEC 60050-445:2010, 445-04-03]
3.1.12
on-state voltage drop of a solid-state output circuit
voltage drop of a solid-state output circuit (deprecated)
voltage measured across the effectively conducting solid-state output of a time relay, when
carrying the given load current
[IEC 60050-445:2010, 445-04-04]
3.1.13
leakage current of a solid-state output
off-state current of a solid-state output (deprecated)
electric current which flows through the effectively non-conducting solid-state output of a time
relay at a specified voltage
[IEC 60050-445:2010, 445-04-05]
3.1.14
power port
point at which the supply voltage (either a.c. or d.c.) is connected to the time relay
[IEC 60050-445:2010, 445-07-01]
3.1.15
control port
additional port for the starting of functions whilst supply voltage is applied, or for the
connection of a remote potentiometer, control signal, etc.
NOTE There are control ports for floating (potential-free) and non-floating control.

61812-1  IEC:2011 – 11 –
[IEC 60050-445:2010, 445-07-02]
3.1.16
output port
port at which a load is connected to the time relay
NOTE The output port could consist of electromechanical contacts or be a solid-state output.
[IEC 60050-445:2010, 445-07-03]
3.1.17
enclosure port
physical boundary of the time relay through which electromagnetic fields can radiate or
impinge
[IEC 60050-445:2010, 445-07-04]
NOTE See Figure 1.
Enclosure port
Power port Output port
Time relay
Control port
(if any)
IEC  792/11
Figure 1 – Definition of ports
3.2 Terms and definitions of relay types

Key
Power supply
Control signal
T Setting time
Make contact
IEC  793/11
Figure 2 – Definition of symbols
3.2.1
power on-delay relay
on-delay relay
time relay in which the time delay starts when applying the power supply and the output
switches to the operate condition after the setting time has elapsed (see Figure 2 and
Figure 3)
– 12 – 61812-1  IEC:2011
T
Time
IEC  794/11
Figure 3 – Power on-delay relay
[IEC 60050-445:2010, 445-01-02]
3.2.2
power off-delay relay
true off-delay relay
time relay in which the output immediately switches to the operate condition when applying
the power supply; the time delay starts when the power supply is removed; the output
switches to the release condition after the setting time has elapsed (see Figure 2 and
Figure 4)
T
Time
IEC  795/11
Figure 4 – Power off-delay relay
[IEC 60050-445:2010, 445-01-03]
3.2.3
off-delay relay with control signal
off-delay relay
time relay in which the output immediately switches to the operate condition when applying
the power supply and the control signal; the time delay starts when removing the control
signal, and the output switches to the release condition after the setting time has elapsed
(see Figure 2 and Figure 5)
NOTE Effects of subsequent operating or resetting of the control signal should be declared by the manufacturer.

T
Time
IEC  796/11
Figure 5 – Off-delay relay with control signal
[IEC 60050-445:2010, 445-01-04]

61812-1  IEC:2011 – 13 –
3.2.4
on- and off-delay relay with control signal
time relay in which the output switches to the operate condition when applying the power
supply and the control signal and after the setting time has elapsed; the output switches to
the release condition when the control signal is removed and after the setting time has
elapsed (see Figure 2 and Figure 6)
NOTE Effects of subsequent operating or retriggering of the control signal should be declared by the
manufacturer.
T T
Time
IEC  797/11
Figure 6 – On- and off-delay relay with control signal
[IEC 60050-445:2010, 445-01-05]
3.2.5
flasher relay
repeat cycle relay
time relay in which the output periodically switches on and off as long as the power supply or
control signal is applied (see Figure 2 and Figure 7)
NOTE 1 Depending on the relay type, the output starts with "pulse on" or "pulse off".
NOTE 2 Flasher relay may also be initiated with a control signal.

T T T T T T
1 2 1 2 1 2
t < T
Time
IEC  798/11
Figure 7 – Flasher relay
[IEC 60050-445:2010, 445-01-06]
3.2.6
symmetrical flasher relay
symmetrical repeat cycle relay
flasher relay in which the output periodically switches on and off with substantially identical
durations of pulse on time and pulse off time
[IEC 60050-445:2010, 445-01-07]
3.2.7
asymmetrical flasher relay
asymmetrical repeat cycle relay
flasher relay in which the pulse on time and pulse off time are selectable separately

– 14 – 61812-1  IEC:2011
[IEC 60050-445:2010, 445-01-08]
3.2.8
star-delta relay
time relay including two delayed outputs switching one after the other, for starting of motors in
the star mode and subsequent change to the delta mode (see Figure 2 and Figure 8)
NOTE The star and delta connections are defined in IEC 60050-141:2010, 141-02-06 and IEC 60050-141:2010, 141-02-
09 respectively.
T
S
T
D
Time
IEC  799/11
Figure 8 – Star-delta relay
[IEC 60050-445:2010, 445-01-09]
3.2.9
summation time relay
time relay in which the output switches when the setting time has elapsed by summation of
the time periods during which the control signal has been applied (see Figure 2 and Figure 9)

T
1 T
T = T + T
1 2
Time
IEC  800/11
Figure 9 – Summation time relay
[IEC 60050-445:2010, 445-01-10]
3.2.10
pulse delayed relay
time relay in which the time delay starts when applying the power supply; the output
momentarily switches for an interval to the operate condition after the time delay has elapsed
(see Figure 2 and Figure 10)
NOTE Manufacturer should specify if interval is fixed or variable.

61812-1  IEC:2011 – 15 –
T
Time
IEC  801/11
Figure 10 – Pulse delayed relay
[IEC 60050-445:2010, 445-01-11]
3.2.11
pulse delayed relay with control signal
time relay in which the time delay starts when applying the power supply and the control
signal; the output momentarily switches for an interval to the operate condition after the
setting time has elapsed (see Figure 2 and Figure 11)
NOTE 1 Cycling the control signal during the time delay will not retrigger the time delay.
NOTE 2 Manufacturer should specify if interval is fixed or variable.

T
Time
IEC  802/11
Figure 11 – Pulse delayed relay with control signal
[IEC 60050-445:2010, 445-01-12]
3.2.12
interval relay
time relay in which the output immediately switches to the operate condition and the time
delay starts when applying the power supply, and the output switches to the release condition
after the setting time has elapsed (see Figure 2 and Figure 12)

T
Time
IEC  803/11
Figure 12 – Interval relay
[IEC 60050-445:2010, 445-01-13]

– 16 – 61812-1  IEC:2011
3.2.13
interval relay with control signal
single shot relay
time relay in which the output immediately changes to the operate condition and the time
delay starts when applying the power supply and the control signal; the output switches to the
release condition after the setting time has elapsed (see Figure 2 and Figure 13)
NOTE Cycling the control signal during the time delay will not retrigger the time delay.

T T
Time
IEC  804/11
Figure 13 – Interval relay with control signal
[IEC 60050-445:2010, 445-01-14]
3.2.14
retriggerable interval relay with control signal on
watchdog relay
time relay in which the output immediately switches to the operate condition and the time
delay starts when applying the power supply and the control signal; the output switches to the
release condition after the setting time has elapsed and if the control signal is not operated
during the setting time (see Figure 2 and Figure 14)
NOTE Cycling the control signal during the time delay will retrigger the time delay.

T t < T T
Time
IEC  805/11
Figure 14 – Retriggerable interval relay with control signal on
[IEC 60050-445:2010, 445-01-15]
3.2.15
retriggerable interval relay with control signal off
fleeting off delay relay
time relay in which the output immediately changes to the operate condition and the time
delay starts when applying the power supply and removing the control signal; the output
switches to the release condition after the setting time has elapsed (see Figure 2 and
Figure 15)
NOTE Cycling the control signal during the time delay will retrigger the time delay.

61812-1  IEC:2011 – 17 –
T t < T T
Time
IEC  806/11
Figure 15 – Retriggerable interval relay with control signal off
[IEC 60050-445:2010, 445-01-16]
3.2.16
maintained time relay
time relay which does not prematurely release if the energizing quantity is removed and the
time interval is not concluded (see Figure 2 and Figure 16)

T
Time
IEC  807/11
Figure 16 – Maintained time relay
[IEC 60050-445:2010, 445-01-17]
4 Influence quantities
The specified performance of a relay shall be given with respect to the reference conditions,
i.e. the set of reference values of all influence quantities.
Unless otherwise explicitly stated by the manufacturer, the values and tolerance ranges listed
in Table 1 apply.
Table 1 – Influence quantities and reference values
Influence quantities Reference values for Tolerances during tests
tests
Ambient temperature 23 °C ± 5 °C
Air pressure 96 kPa
± 10 kPa
Relative humidity 50 % ± 25 %
Position As indicated by the 2° in any direction
manufacturer
Input voltage Rated value(s)
± 5 % for steady-state
a
conditions
Output circuit Rated value(s) ± 5 % for steady-state
(voltage/current) conditions
Frequency As indicated by the
± 1 %
manufacturer
– 18 – 61812-1  IEC:2011
Influence quantities Reference values for Tolerances during tests
tests
Waveform Sinusoidal Maximum distortion factor
b
5 %
Direct component in a.c. As indicated by input Max. 2 % of peak value
voltage
c
Alternating component in As indicated by i
...