Fig. 53 Par. 1.14H

ELECTRICAL DEVICE NUMBERS AND THEIR FUNCTIONS (Continued)

Sheet 2

DEVICE
NO.

FUNCTION OF DEVICES

ACCELERATING OR DECELERATING CONTACTOR, CIRCUIT BREAKER, OR RELAY is one which causes the operation of a succeeding device in the starting sequence after the proper conditions have been established.

STARTING-TO-RUNNING TRANSITION CONTACTOR OR RELAY is one which gives an impulse to main circuit devices for changing a machine from the starting to the running connections.

ELECTRICALLY OPERATED VALVE is a solenoid or motor-operated valve either in vacuum, air, oil, or waterline. When several different types of electrically operated valves are furnished on one equipment, they will be designated as follows:

20 A Electrically operated valve for air
20 Q Electrically operated valve for oil
20 V Electrically operated valve for vacuum
20 W Electrically operated valve for water.

IMPEDANCE RELAY.

EQUALIZER CIRCUIT BREAKER OR CONTACTOR is a device which makes equalizer connections for multiple unit equipments.

TEMPERATURE REGULATING DEVICE is a thermal relay which operates to hold temperature between given limits.

BUS-TIE CIRCUIT BREAKER, CONTACTOR, OR SWITCH is a device used to connect a-c or d-c buses together.

SYNCHRONIZING OR PARELLELING DEVICE.

APPARATUS THERMAL DEVICE is one which functions when given value of heating of the apparatus to which it is applied has been reached.

A-C UNDERVOLTAGE RELAY is one which functions on a given value of a-c line or control voltage.

RESISTOR THERMAL DEVICE is one which functions when a given value of heating of the load indicating, load shifting, or load limiting resistors has been reached.

ISOLATING CIRCUIT BREAKER, CONTACTOR, OR SWITCH is a device used for completely disconnecting one circuit from another, generally during emergency operation or test.

ANNUNCIATOR RELAY is a nonautomatic-reset device which gives individual visual indications upon the functioning of lockout protective devices, and may also be arranged to perform the lockout function in the master control circuit.

SEPARATE EXCITATION DEVICE is one which connects a converter shunt field to a source of separate excitation.

D-C REVERSE POWER RELAY is one which functions on a given value of direct-current power reversal.

POSITION SWITCH is one which indicates position of waterwheel gate. MOTOR-OPERATED SEQUENCE SWITCH is a motor-operated device which fixes sequence of major devices during starting and stopping sequence.

ELECTRICAL DEVICE NUMBERS AND THEIR FUNCTIONS (Continued) Fig. 53 Par. 1.14H

Sheet 3

DEVICE

NO.

FUNCTION OF DEVICES

BRUSH-OPERATING OR SLIP-RING SHORT CIRCUITING DEVICE is one
for raising, lowering, or shifting the brushes of a machine, or for short
circuiting the slip rings.

POLARITY RELAY is one which indicates polarity.

UNDERCURRENT OR UNDERPOWER RELAY is one which functions on
a given minimum value of current or power flow.

BEARING THERMAL DEVICE is one which functions upon excessive
bearing temperature.

FIELD-REDUCING CONTACTOR is one which inserts resistance in
field of machine.

FIELD RELAY is one which indicates presence or loss of field in a
machine.

FIELD CIRCUIT BREAKER, CONTACTOR, OR SWITCH is a device which
functions to apply, remove, or reverse a machine field.

RUNNING CIRCUIT BREAKER, CONTACTOR, OR SWITCH is a device
which connects a machine to source of running voltage.

TRANSFER DEVICE is a device which transfers control of breakers,
etc., from automatic to test switches, or control of equipment from
manual to automatic, automatic to continuous, or performs some
transfer operation other than unit sequence.

UNIT SEQUENCE STARTING CONTACTOR OR RELAY is one which
functions to start the next available unit, in multiple unit equipment on
failure or overload of normally preceding unit.

D-C OVERVOLTAGE RELAY is one which functions on a given value of
d-c machine or bus overvoltage.

REVERSE-PHASE OR PHASE-BALANCE CURRENT RELAY OR POWER-
RECTIFIER MISFIRE RELAY is one which functions on an unbalanced
current condition, or on reverse phase flow of current, or on misfire of
power rectifier.

SINGLE OR REVERSE-PHASE VOLTAGE RELAY is one which functions
upon presence of correct polyphase voltage, or upon polyphase voltage
of correct phase rotation, or both.

INCOMPLETE SEQUENCE RELAY is one which gives indication to shut
down a machine and prevent its restarting if the control does not
properly complete a predetermined sequence.

A-C THERMAL RELAY is a thermal device which functions when the
temperature of a-c apparatus controlled tends to decrease below or
increase above the safe operating value.

SHORT-CIRCUIT SELECTIVE RELAY is one which functions on excessive
rate of rise of current and may further allow reclosing only after normal
conditions have been reestablished.

51

A-C OVERCURRENT RELAY is one which functions when current in an
a-c circuit exceeds a given value.

Fig. 53 Par. 1.14H

ELECTRICAL DEVICE NUMBERS AND THEIR FUNCTIONS (Continued)

Sheet 4

DEVICE
NO.

53

54

55

FUNCTION OF DEVICES

EXCITER OR GENERATOR RELAY is one which indicates operating values of exciter armature voltage or current or generator voltage, or insures positive building up of exciter or generator voltage, or indicates presence of generator field.

HIGH-SPEED CIRCUIT BREAKER is a circuit breaker which starts to open the main circuit in 0.01 second or less on excessive rate of rise of current or on d-c overload above its setting.

POWER-FACTOR RELAY is one which holds or indicates a given power factor on an a-c machine or system.

59

60

61

62

63

64

65

66

67

A-C OVERVOLTAGE RELAY is one which functions on a given value of a-c overvoltage.

VOLTAGE-BALANCE RELAY is one which indicates, or functions to hold, a given voltage difference between two sources of voltage.

CURRENT-BALANCE RELAY is one which indicates, or holds, a given current relation between two sources of current.

TIME-DELAY STOPPING OR OPENING RELAY is one which affords the required time delay in the sequence of taking an equipment out of operation.

FLUID-PRESSURE OR FLOW RELAY is one which indicates presence, value or failure of oil, water, vacuum, or air pressure. May be used as a regulating or protective relay, or both.

When several different types of pressure relays are furnished as one equipment, they will be designated as follows:

No. 63A Pressure relay for air
No. 63Q Pressure relay for oil
No. 63V Pressure relay for vacuum
No. 63W Pressure relay for water.

GROUNDING PROTECTIVE RELAY is one which functions on failure of machine insulation to ground or flashover of d-c machine to ground.

GOVERNOR is the speed regulating device for a prime mover. Complete
electrically operated governor parts are as follows:

65-A-Governor Accelerating Device (used during starting)
65-MF-Governor Fly Ball Motor

65-ML-Governor Load Limit Motor

65-MS-Governor Synchronizing Motor

65-S-Governor Solenoid.

NOTCHING RELAY is one which functions to allow only a specified number of operations of a given device, or equipment, or a specified number of successive operations within a given time of each other. Also is used to allow periodic energizing of a circuit.

A-C POWER-DIRECTIONAL OR A-C POWER-DIRECTIONAL OVER-
CURRENT RELAY.

ELECTRICAL DEVICE NUMBERS AND THEIR FUNCTIONS (Continued)

Fig. 53 Par. 1.14H
Sheet 5

DEVICE
NO.

FUNCTION OF DEVICES

D-C THERMAL RELAY is a thermal device which functions when the
temperature of the d-c apparatus controlled tends to exceed a safe
operating value.

PERMISSIVE CONTROL DEVICE.

ELECTRICALLY OPERATED RHEOSTAT is one used primarily to
vary the resistance of a circuit in response to some contact-making
device.

D-C LINE EMERGENCY CIRCUIT BREAKER OR CONTACTOR is one
used to interrupt a d-c power circuit under emergency conditions.

D-C LINE CIRCUIT BREAKER OR CONTACTOR is one used to close
and interrupt a d-c power circuit under normal conditions or to interrupt
this circuit under emergency conditions.

LOAD RESISTOR CIRCUIT BREAKER OR CONTACTOR is one used to
insert a step of load limiting resistance in a power circuit under abnor-
mal or overload conditions and to shunt this step of resistance when the
abnormal or overload condition has disappeared.

73-1 for breaker or contactor shunting first step of resistance in
sequence if more than one

73-2 for breaker or contactor shunting second step of resistance
in sequence

73-3 for breaker or contactor shunting third step of resistance in

sequence

73-4 for breaker or contactor shunting fourth step of resistance in
sequence.

ALARM RELAY.

POSITION-CHANGING MECHANISM FOR REMOVABLE CIRCUIT-
BREAKER UNIT.

D-C OVERCURRENT RELAY is one which functions on a d-c overload
above a given amount. It may also be provided with specified dropout
value so as to reclose load limiting resistor shunting circuit breaker
or contactor, No. 73 for example,.when the overload has disappeared.

76-1 functions with 73-1
76-2 functions with 73-2
76-3 functions with 73-3

76-4 functions with 73-4.

IMPULSE TRANSMITTER.

PHASE-ANGLE MEASURING RELAY.

A-C RECLOSING RELAY is a device which controls the reclosing of
an a-c circuit interrupter.

D-C UNDERVOLTAGE RELAY is one which functions at a given value
of d-c undervoltage.

FREQUENCY DEVICE.

D-C RECLOSING RELAY is one which controls the reclosing of a d-c
circuit interrupter.

Fig. 53 Par. 1.14H

ELECTRICAL DEVICE NUMBERS AND THEIR FUNCTIONS (Continued)

Sheet 6

DEVICE
NO.

83

FUNCTION OF DEVICES

SELECTIVE CONTROL CONTACTOR OR RELAY is one which selects between certain sources or conditions in an equipment.

86

87

88

89

90

91

92

93

94

CARRIER OR PILOT-WIRE RECEIVER RELAY.

LOCKING-OUT RELAY is one which locks out equipment on abnormal conditions.

DIFFERENTIAL CURRENT RELAY is one which functions on differential current of a given amount.

AUXILIARY MOTOR OR MOTOR-GENERATOR is used for operating equipment accessories such as pumps, blowers, etc.

When auxiliary motors or motor generators are furnished on one equipment for several different accessories, they should be designated as follows:

No. 88 B Auxiliary motor or motor generator for blower
No. 88Q Auxiliary motor or motor generator for oil pump
No. 88 V Auxiliary motor or motor generator for vacuum
No. 88 W Auxiliary motor or motor generator for water.

LINE SWITCH is one used as a disconnecting switch in a d-c power circuit.

D-C VOLTAGE DIRECTIONAL RELAY functions when the d-c voltage exceeds a certain amount in a given direction.

D-C VOLTAGE AND CURRENT-DIRECTIONAL RELAY is one used to give indication to close a circuit when the voltage exceeds a certain amount in a given direction, and to give the indication to open this circuit when the current exceeds a certain amount in the reverse direction.

FIELD-CHANGING CONTACTOR OR RELAY is one which functions to change the amount or source of excitation on a machine.

TRIPPING OF TRIP-FREE RELAY OR CONTACTOR is one which
functions as a tripping contactor to trip out the equipment. (As a
trip-free relay, it functions to prevent immediate reclosure of a circuit
interrupter, in case it opens immediately upon overload, even though
the original closing circuit is still held closed.)

A similar series of numbers starting with 101 instead of 1 is used for the functions which apply to feeder equipments.