Advertisement
CV Voltage Relay Class 1E
two stationary contacts, completing the trip circuit.
For double circuit closing contacts, the moving con-
tacts bridge three stationary contacts. Also during
this operation two fingers on the armature deflect a
spring located on the front of the switch, which allows
the operation indicator target to drop.
The same unit is also used as a Trip Indicator (OI)
except there are no stationary contacts, or the sta-
tionary contacts are moved upward out of reach of
the moving contacts.
The front spring in addition to holding the target, pro-
vides restraint for the armature and thus controls the
pickup value of the switch.
3.0 CHARACTERISTICS
The low pickup CV-8 Overvoltage Relay is available
with the following continuous voltage ratings.
Type Relay
67 volts
199 volts
The minimum 60 Hertz voltage to just close the CV-8
contacts is typically 8% of the continuous voltage.
Typical operating times of the type CV-8 relay are
shown on Figure 11 (page 13). An adjustable 5.4 to
20 volt relay with a 67 volt continuous and a 16 to 40
volt relay with a continuous of 199 volts is also avail-
able. However, the operate times for the adjustable
CV-8 relay will differ from Figure 11 and will depend
on the pickup setting. Figure 12 (page 14) applies
when the resistor is set for maximum pickup. Pickup
changes with frequency as shown in Figure 13 (page
15).
The CV-1 and CV-2 Undervoltage Relays, CV-4 and
CV-5 Overvoltage Relays, and CV-6 and CV-7 Over
or Under voltage Relays are available in the following
voltage ranges.
Range
55-140
55
64
70
110-280
110
128
140
3.1. CV-1 AND CV-2 UNDERVOLTAGE RELAYS
CV-4 AND CV-5 OVERVOLTAGE RELAYS
Tap value voltage is the minimum voltage required to
just close the relay contacts. At this value of voltage,
2 Minute Rating
140 volts
300 volts
Taps
82
93
105
120
140
164
186
210
240
280
the moving contacts will leave the backstop of the
time dial and move to close the front contacts. Nor-
mal operation of the two relays is such that the CV-1
and CV-2 undervoltage relay will open its contacts
with application of voltages greater than tap value
voltage, while the CV-4 and CV-5 overvoltage relay
closes its contacts with voltages greater than tap
value voltage. Thus, the operating curves of Figures
14 and 15 (page 16) of the undervoltage relays apply
when the voltage is originally higher than tap value
voltage and is suddenly reduced to a value shown on
the curves. The operating curves of Figures 16 and
17 (page 19) of the overvoltage relays apply when
the voltage is initially below tap value voltage and is
suddenly raised to a value shown on the curves.
3.2. CV-6 AND CV-7 OVER OR
UNDERVOLTAGE RELAYS
Tap value voltage is the value of voltage at which the
stationary front contact closes. The stationary back
contact will close within 5% of this value.
When the relay is used as an overvoltage relay, the
moving contact is made with the stationary back con-
tact for values of applied voltage less than tap value
voltage. With application of voltages greater than tap
value voltage, the moving contact moves to close the
front contact in a time as shown by the right-hand
curves of either Figures 18 or 19 (page 20).
When the relay is used as an undervoltage relay, the
moving contact is made with the stationary front con-
tact for values of applied voltage greater than tap
value voltage. With the application of voltages less
than tap value voltage, the moving contact moves to
close the back contact in a time as shown on the left-
hand curves of either Figures 18 or 19 (page 20).
3.2.1. Auxiliary Relays (T)
Power Requirements
Per Unit:
1.3 watts at 48 volts dc
3.3 watts at 125 volts dc
Operate Time
Pick Up:
3 to 6 milliseconds
Drop Out:
90 to 130 milliseconds
Contact Rating:
A. 20 amperes
B. 1.3 amperes resistive at
C. Will control MG-6, SG, or AR
41-201.4H
noninterrupting for less than
200 milliseconds
125Vdc
relays at 125Vdc
3
Advertisement
