GB 14048.4-1993 Low-voltage switchgear and control equipment Low-voltage electromechanical contactors and motor starters
Some standard content:
National Standard of the People's Republic of China
Low-voltage switchgear and controlgear
Low-voltage electromechanical contactors and motor starters Low-voltage swltchgear and controlgear-Low-voltageelectromechanical contactors and motor startersGB14048.4-93
This standard is equivalent to IEC947-4-1 (1990) "Low-voltage switchgear and controlgear Part 4 Contactors and motor starters Part 1 Electromechanical contactors and motor starters". 1 Subject content and scope of application
This standard specifies the common basic requirements for low-voltage electromechanical contactors and motor starters, including characteristics, working conditions, performance and tests and test methods to verify that the electrical appliances meet these requirements. It also specifies the parameters that should be marked on the electrical appliances or the data that the manufacturer should provide, as well as packaging, transportation and storage requirements.
This standard applies to contactors and starters with main contact rated voltages of 50Hz, 1140V (1200V) and below, and 1500V (1650V) and below, as specified in Article 1.1. Mainly includes: 1.1 AC and DC contactors
AC and DC contactors are used to connect and disconnect circuits, and are combined with appropriate thermal overload relays to protect circuits that may be overloaded during operation (running).
This standard also applies to special contacts for contactor coil circuits. 1.2 AC motor starters
AC motor starters are used to start motors and accelerate motors to rated speeds, ensure continuous operation of motors, protect motors and related circuits from overload operation (running), and artificially disconnect the power supply circuits of motors. 1.2.1 Direct (full voltage) starters (including reversible starters) 1.2.2 AC reduced-voltage starters
1.2.2.1 Star-delta starters.
1.2.2.2 Two-stage auto-coupling starter.
1.2.3 Rotor variable resistance starter
Note: The typical curves of current, starting torque and driving mechanical torque of star-delta starter and two-stage auto-coupling starter are shown in Figures 1 and 2. Approved by the State Bureau of Technical Supervision on September 5, 1993 and implemented on April 1, 1994
Electricity/rated working telephone
5
3-
GB14048.4-93
I
0.8
Step speed
Transfer/rated rotation speed
Ip—Current in triangle connection; I—Current in star connection 1Torque/rated torque
Tu
Synchronous speed
Tuy
5
0.8
Special speed/rated speed
Figure 1 Typical current and torque curves during star-delta starting TMD-Motor torque in delta connection: TMYMotor torque in star connection: Tr-Load torque
Device,
Current/rated working current
F
I.0.8 tap
I.0.65 tap
IL0.5 tap
GB14048.4-93
I,0.8 tap
I.0.5 tap
I,0.65 tap
0.8
Synchronous speed
Speed/fixed speed||tt ||Ir-motor current at rated voltage: Ir-motor current after decompression; I-line current after decompression
Special torque/rated torque
TaTO.65 tap
0.8
Synchronous speed
Speed/rated speed
Figure 2 Typical curve of current and torque during auto-decompression starting IR-load torque; TMR-motor torque at rated voltage; TMY-motor torque after decompression
This standard does not apply to the following electrical appliances
a.
b.
c.
d.
e.
f.
g.
h.
i.
DC starters;
star-delta starters for special purposes and continuous operation in the starting position, rotor rheostat starters and two-stage autotransformer pressure-reducing starters with more than two stages;
unbalanced (i.e., the resistance values ??of each phase are different) rotor rheostat starters; starters used not only for starting but also for speed regulation, liquid starters and "liquid-gas" starters, semiconductor contactors and starters using semiconductor contactors in the main circuit; stator rheostat starters;
contactors and starters for special purposes.
2 Reference standards
GB/T14048.11
General rules for low-voltage switchgear and controlgear
GB14048.5 Control circuits and switch elements for low-voltage switchgear and controlgear Part 1 Electromechanical control circuits and switch elements
GB2900.18
Electrical terminology Low-voltage electrical appliances
GB14048.4-93
GB2423.4 Basic environmental test procedures for electrical and electronic products Test Db: Alternating damp heat test method GB5169.4 Fire hazard test for electric and electronic products Glowing wire test method and guide GB14048.2 Low-voltage switchgear and control equipment Low-voltage circuit breakers GB13539.1~13539.4 Low-voltage fuses Note: This standard quotes many requirements and test methods in GB/T14048.1. This standard should be used in conjunction with this standard. When quoting, this standard indicates the quoted clause number, such as: 8.2.2.1 in GB/T14048.1 is applicable. 3 Terms, symbols, and codes
3.1 Terms
For terms not specified in this standard, please refer to the relevant terms and definitions in GB2900.18. 3.1.1 Terms related to contactors
3.1.1.1 (of a contactor) rest position Position of rest (of a contactor) The position of the movable part of the contactor when the electromagnet or compressed air device of the contactor is not energized. 3.1.2 Terminology related to starters
3.1.2.1 Two-direction starter Two-direction starter A starter that reverses the original wiring of the motor only when the motor stops to reverse the motor. 3.1.2.2 Reduced voltage starter A starter that applies the line voltage to the motor terminals by using more than one level or gradually increases the voltage applied to the motor terminals.
3.1.2.3 Rheostatic stator starter A rheostatic starter that sequentially cuts off one or more resistors pre-connected in the stator circuit of the cage motor during starting. 3.1.2.4 Combination starter A device composed of a human-operated switch and a short-circuit protection device installed and connected in a dedicated housing outside the starter. The switch and short-circuit protection device can be a fuse combination device, a switch with a fuse, or a circuit breaker with or without isolation function (see Figure 3). Note: ① The special housing is a housing specially designed and selected in size according to the usage, and it should meet all the corresponding tests; ② The manually operated switch and short-circuit protection can be a single appliance or include overload protection. 3.1.2.5 The protected starter is composed of a starter, a manually operated switch and a short-circuit protection, and is installed and wired according to the regulations of the starter manufacturer, with or without a housing (see Figure 3).
Note: The manually operated switch and short-circuit protection can be a single appliance or include overload protection. 3.1.2.6 Starting time (of varistor starter) Starting time (of arheostatic starter) Current carrying time of the starting resistor or part of the starting resistor during starting. 3.1.2.7 Starting time (of an auto-transformer starter) Starting time (of an auto-transformer starter) Current carrying time of the autotransformer during starting. Note: For 3.1.2.8 and 3.1.2.9, the starting time of the starter is shorter than the starting time of the motor, which includes the final acceleration process of the motor when the switch is in the running position
3.1.2.8 Open transition (with an auto-transformer starter or star-delta starter) The circuit is designed so that when the starter is switched from one stage to another, its power supply is disconnected and then connected. Note: This transition is not considered an additional stage.
3.1.2.9 Closed transition (with an auto-transformer starter or star-delta starter) The circuit is designed so that when the starter is switched from one stage to another, its power supply is not disconnected (even for a moment). Note: This transition is not considered an additional stage.
3.2 Symbols
GB14048.4—93
Figure 3 Typical types of integrated starters and protected starters (3.1.2.4 and 3.1.2.5) 1-circuit breaker; 2-contactor, 3-overload relay; 4-control switch 5-circuit breaker with electromagnetic release only; 6-high isolation switch, 7 fuse; 8-isolator fuse group, 9-circuit breaker with overload release in accordance with this standard 3.2 of GB/T14048.1 is applicable, supplemented by the following symbols: U connection voltage;
U. Rated working voltage:
Ue stator rated working voltage;
Ue rotor rated working voltage;
U. Stator rated insulation voltage,
U. Rotor rated insulation voltage,
U, (power frequency or DC) recovery voltage after disconnection, U rated control power supply voltage;
Switching on current:
1bzxz.net
Irated working current;
I
On-off current:
Stator conventional thermal current;
Ith
Ithr Rotor conventional thermal current;
1 Stator rated working current,
Ir Rotor rated working current,
cos Power factor of test circuit;
Time constant of L/R test circuit;
T. Tripping time;
AC alternating current;
DC direct current;
Db alternating damp heat test;
SCPD short-circuit protection device;
CTI
Comparative tracking index.
3.3 Code
GB14048.4—93
The commonly used categories and codes for the main circuits of contactors and motor starters are shown in Table 1. 3.3.1
Table 1 Commonly used categories and codes for the main circuits of contactors and motor starters Current
Ac
DC
Use category code
Ac-1
AC-2
A C-3
AC-4
AC-5a
AC-5b
AC-6a
AC-6b
AC-7a
AC-7b
AC-8a
AC-8b
DC-1
DC-3
DC-5
DC-6
4 categories
Non-inductive or slightly inductive Load, resistance furnace
Starting and disconnection of wound-rotor induction motorsStarting and disconnection of cage-type induction motors during operationTypical application examples
Starting, reverse braking or reverse operation, and inching of cage-type induction motorsOn and off of discharge lamps
On and off of incandescent lamps
On and off of transformers
On and off of capacitor banks
Low inductive loads for household appliances and similar purposesHousehold motor loads
Motor control in sealed refrigeration compressors with manual reset overload releaseMotor control in sealed refrigeration compressors with automatic reset overload releaseNon-inductive or slightly inductive load, resistance furnace
Starting, reverse braking or reverse operation, inching, and disconnection of motors in motionStarting, reverse braking or reverse operation, inching, and disconnection of motors in motionIncandescent lamps on and off
The types and models of electrical appliances in Article 5.2 of this standard can be used as the basis for classification. 5 Characteristics
5.1 Summary of characteristics
GB14048.4—93
The characteristics of contactors and starters are specified by the following items (when applicable): a
b.
c.
d.
e.
f.
g.
h.
1.
Type and type of electrical appliance (5.2);
Rated value and limit value of main circuit (5.3); Category of use (5.4);||tt t||Control circuit (5.5);
Auxiliary circuit (5.6),
Types and characteristics of relays and releases (5.7); Coordination with short-circuit protection devices (5.8); On-off operation overvoltage (5.9);
Types and characteristics of automatic conversion devices and automatic acceleration control devices (5.10), types and characteristics of autotransformers of two-stage autotransformer step-down starters (5.11);j
k.
Types and characteristics of starting resistors of rotor variable resistance starters (5.12). 5.2 Types and models of electrical appliances
5.2.1 Types of electrical appliances
5.2.1.13
AC and DC contactors
5.2.1.2 AC motor starters
AC direct starter;
a.
b.
c.
d.
Star-delta starter;
Two-stage autocoupler step-down starter;
Rotor rheostatic starter;
Combined starter or protected starter. 5.2.2
Number of poles
5.2.3 Type of current (AC or DC, AC including frequency)5.2.4 Arc extinguishing medium
5.2.5 Operating conditions of electrical appliances
5.2.5.1 Mode of operation (manual, electromagnet, motor, pneumatic, electro-pneumatic)5.2.5.2 Mode of control
Automatic (controlled by master switch or program controller); a.
Non-automatic (manual operation or button operation); b.
c.
Semi-automatic (partially automatic and partly non-automatic control). 5.2.5.3 (Partial type)) Conversion mode of starter The conversion of star-delta starter, rotor rheostat starter or auto-coupling pressure reducing starter can be automatic, non-automatic or semi-automatic (see Figures 4 and 5).
Mechanical switch circuit
CL
CCR
CRR
Stop
0
o
o
CCR
GB14048.4—93
CL
CRR.d
Starter position
Start
First level
c
o
0
O-Mechanical switch electrical appliance disconnected; C--Mechanical switch electrical appliance Closed second stage
c
0
c
Moving
Third stage
(full start)
c
c
c
Figure 4 Example of a three-phase circuit diagram of a rotor rheostatic starter with three starting stages and one direction of rotation (all mechanical switching devices are contactors) ZB
ZE
GB14048.4—93
ZB
Autotransformer: M-motor; K,,K.,K, the contact action sequence of a contactor or other mechanical switching appliance
Contact
R
K
R
Start|| tt||C
C-Contact closure
Conversion
c
0
Operation
0
C
Contact
K
K
K
Start
c
C
o| |tt||Contact action sequence
Open circuit conversion
o
0
0
Closed circuit conversion
1||tt| |0
c
0
2
0
c
c
run
0
c
For open circuit conversion K and K, they can be the contacts of the same mechanical switching appliance
Contacts
K
K||tt ||K
Contact action sequence
Start
C
Conversion
0
0
Operation|| tt | | 0 | Typical methods of cage motors and their schematic diagrams 5.2.5.4 Connection methods of (partial types) starters. Examples of starters with open circuit conversion or closed circuit conversion are shown in Figure 5. 5.3 Ratings and limit values ??of the main circuit
contact The ratings of motors and starters shall be expressed in accordance with the provisions of 5.3, 5.4, 5.8 and 5.9, and may be increased or decreased as necessary. 5.3.1 Rated voltage
The rated voltage of contactors and starters is specified as follows: 5.3.1.1 Rated operating voltage (U)
5.3.1.1 in GB/T14048.1 applies.
5.3.1.1.1 Stator rated working voltage (U) The stator rated working voltage of the rotor rheostat starter and the stator rated working current together determine the purpose of the stator circuit (including its mechanical switching appliances), and through Breaking capacity, working system and starting characteristics are related to it. In no case shall the maximum rated operating voltage exceed the phase
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