ABB CVQ Instruction Leaflet

ABB Automation Inc.
Substation Automation and Protection Division
ABB
ABB
ABBABB
Effective: October 1999 Supersedes I.L. 41-223L, dated January 1996
( ) Denotes Change Since Previous Issue
CAUTION
!
Before putting protective relays into service, remove all blocking inserted for the purpose of securing the parts during shipment. Make sure that all moving parts operate freely. Inspect the contacts to see that they are clean and close properly, and operate the relay to check the set­tings and electrical connections.
Coral Springs, FL 33065

1.0 APPLICATIONS

The type CVQ relay prov ide s instan tan eous an d ti me delay detection of negativ e sequence ove rvoltage as well as responding with tim e del ay to pha se-to-phase undervoltage.
Used in motor protecti on, the relay protects against system undervoltage, single phasing of the supply and reversal of phase rotation of the supply.
Instruction Leaflet
41-223N
Type CVQ Relay
If static (i.e., non motor) load i s single-phase d with a motor or group of motors, the negative sequence volt­age will be greater than the v alue calculated above. Single phasing of a predominately static load pro­duces 50% negative sequence voltage on the load side of the open circuit.
When the relay i s used for overvol tage pr otec tion t he back contacts are made at normal voltage and the negative sequence element is committed to an instantaneous function. The normally open E2 con­tact may be used for alarm purposes.

2.0 CONSTRUCTION & OPERATION

The type CVQ relay consis ts of a polar unit (E) oper ­ating on negative sequence quantities, a negative sequence voltage filter, full wave bridge, a time undervoltage relay (CV), an indicating contactor switch (ICS) and a telep hone relay when used. The principal componen t parts of the rel ay and their lo ca­tion are shown in Figure 1 (page 2).
The volt-time ch aracteristic of the re lay is that of the CV-7 relay, and t he negative sequence overvolt age pickup is adjustable from 5 to 10 percent of rated
to neutral
When one of the thre e supply circuits to a motor is opened, a negative se quence voltage will appear on the motor side of the open which is approximately equal to I current flowing pr ior to opening the phase and I the motor starting cur rent. For mo st induc tion motor s this will produce approximately 6% negative sequence voltag e ev en if s in gle pha si ng o ccur s at no load because of the effect of the magnetizing require­ment of the motor.
All possible contingencies which may arise during installation, operation or maintenance, and all details and variations of this equ ipment do not purport to be covered by these in structions. If further information is desired by purchase r re gardi ng thi s p artic ul ar in st all ati on, ope ra tio n or maintenance of thi s equ ipment, the local ABB Power T&D Company Inc. representative should be contacted.
voltage.
in per unit where IL is positive seque nc e
L/IS
.
line
S

2.1 POLAR UNIT

The polar unit consists of a recta ngular shap ed mag­netic frame, an electrom agnet, a permanent m agnet, and an armature. The pol es of the crescent shaped permanent magnet bridge the magnetic frame. The magnetic frame consi sts of three piece s joined in the rear with two brass rods and silver solder. These non­magnetic joints repres ent ai r gaps, which are br idged by two adjustable magnetic shunts. The winding or
is
windings are wound around a magnetic core. The armature is fastened to this core and is free to move in the front air gap. The m oving contact is connected to the free end of a leaf spring, which in turn, is fas­tened to the armature.
41-223N CVQ Relay
880A343
*Sub 2
*Sub 4
188A644
Figure 1. Internal Schematic of the Type CVQ Relay Figure 2. Internal Schematic of Type CVQ Relay with Telephone Relay
2
CVQ Relay 41-223N

2.2 NEGATIVE SEQUENCE FILTER

The voltage filter consists of an auto-transformer, reactor, and resistors connected as shown in the internal schematic Figure 1 (page 2).

2.3 VOLTAGE UNIT (CV)

The voltage unit operates on the induction-d isc prin­cipal. A main tapp ed coil l ocate d on the center l eg of an “E” type laminated structure produces a flux which divides and returns t hrough the right le g (front view) to lag the main pole flux. The out-of-phase fluxes thus produced in the air gap causes a contact closing torque.

2.4 INDICATING CONTACTOR SWITCH (ICS)

The indicating contactor switch is a small dc oper­ated clapper type device. A magnetic armature to which leaf-spring mounted contacts are attached is attracted to the magneti c core upon energization of the switch. When th e switch closes , the mov ing con­tacts bridge two stati onary contacts, completing the trip circuit. Also d uring this operation two fi ngers on the armature deflect a spring located on the front of the switch, which al lows the operation indicator tar ­get to drop. The target is reset from the outside of the case by a push-rod located at the bottom of the case.
The front spring, in addition to holding the target, pro­vides restraint for th e armature and thu s controls th e pickup value of the switch.

2.5 FULL WAVE BRIDGE

and 10 percent of the rated line to neutral voltage.
Voltage Unit
which the overvoltage front contact (left-hand, front view) closes. The undervoltage back contact (right­hand, front view) will close within 5% of this value.
When used as an overvoltage relay, the movin g c on­tact is initially at rest ag ai ns t the back contact for val­ues of voltage less than tap value. With application of overvoltage greater th an tap value, the moving con­tact moves to close the front contact in a time as shown by the right-hand cur ves of F igure 3 (page 8).
When energize d and used as an under voltage relay, the moving contact is initially at rest against the front contact for values of voltage greater than tap value. With the reduc tion of voltage to less than t ap value, the moving contact m ove s to clo se the ba ck co nta ct i n a time as shown by the left-hand curves of Figure 3.

3.1 REDUCED FREQUENCY OPERATION

Operation of the E2 unit wil l occur at approximately 54 Hz with rated positiv e sequence voltage applied when set for 5% negative- se quen ce pic kup a t 60 Hz . With a 10% setting, operation occurs at approxi­mately 48 Hz.

3.2 TRIP CIRCUIT

The main contacts will safely close 30 amperes at 250 volts dc and the seal-in contacts of the indicating contactor switch will safely carry this current long enough to trip a circuit breaker.
— Tap value voltage is the value at
The full wave bridge consists of four diodes con­nected to the output o f the negative sequence f ilter. The output is rectified, filtered and fed to the polar unit through an adjus table resistor, which i s used to set the sensitivity of the relay.

2.6 AUXILIARY TIME DELAY UNIT (T) – WHEN USED

This slugged telephone type unit in series with a resistor, provides a 6 to 7 cycle delay on pick-up. The resistor is to be shorted for 48 Vdc operation as shown in the Internal Schematic of Figure 2 (page 2).

3.0 CHARACTERISTICS

Polar Unit
sequence portion of the relay is adjustable between 5
— The sensitivity of the negative
The indicating contactor switch has two taps that pro­vide a pickup setting of 0 .2 o r 2 am peres . To ch ange taps requires conne cting the lead located in front of the tap block to the desired setting by means of a screw connection.

3.3 TRIP CIRCUIT CONSTANTS

Indicating contactor switch – 0.2 amp tap 6.5
ohms dc resistance.
2.0 amp tap 0.15 ohms dc resistance.

4.0 ENERGY REQUIREMENTS

The burden of the undervoltage CV unit at rated volt­age are as follows:
3
41-223N CVQ Relay
Taps
a
Rated
Voltage
120 Volts
a.
These relays will continuously withstand either 110% of
rated voltage or tap value voltage, whichever is higher
120 Vol t
Relay
55 64 70 82
93 105 120 140
Volt
Amps
10.0
7.0
5.8
4.0
3.1
2.4
1.8
1.3
Power Factor Watts
.38 .35 .34 .33 .31 .29 .28 .26
3.8
2.5
2.0
1.3
1.0 .7 .5 .3
.
The burden of the negative sequ ence filter at rated voltage is as follows:
Volt Amperes
Phase 1 Phase 2 Phase 3
58.4
10.5
52.2

5.0 SETTINGS

5.1 POLAR UNIT

The relay will be shipped adjusted for 5% negative sequence sensitivity. Other settings may be made as indicated under Section 8, “
Calibration
”.
The nylon screw o n the terminal plat e holds the tap plate in position when taps are being changed. To use the position on the terminal plate in which the nylon screw is used, remove the nylon screw and place it in one of the unus ed ho les . Then remove the tap screw and insert it in the terminal plate hole.

5.3 MOTOR PROTECTION SETTINGS

For motor protection a tap setting of 75 to 85% of normal line to line volt ages and a time dial setting of 6 or more should be satisfactory for protecting the motor and overriding voltage variations for which trip­ping is not desired.

5.4 NEGATIVE SEQUENCE FILTER

No setting required.

5.5 INDICATING CONTACTOR SWITCH (ICS)

The only setting required on the ICS unit is the selection of the 0.2 or 2.0 ampere tap se tting. This selection is made by connecting the lead located in the front of the tap block to the desired setting by means of the connecting screw. The 0.2 ampere setting is recommended where an au xiliary relay is to be opera ted and the 2.0 ampere settin g is recom­mended where direct tripping of a circuit breaker is to be accomplished.

5.2 CV UNIT

The setting of the CV uni t can be defined either by tap setting and time dial position; or by tap setting and a specific time of op eration at some pe rcentage of tap value voltage (e.g. on CV-7 120 volt tap setting and 2 time dial position; or 120 vo lt tap setting and
1.8 seconds at 140% of tap value volta ge). See fig­ure 3 on page 8.
To provide selective circuit breaker operation, a mini­mum coordinating time of 0.3 seconds plus circuit breaker time is recommended between the relay being set and the relays with wh ic h c oordi nat ion is to be effected.
The connector screw on the term inal plate abo ve the time dial connects vari ous turns of the operati ng coil . By placing this screw in the various terminal plate holes, the relay will just clos e its front c ontact s at the corresponding tap va lue of 55-64-7 0-82-93- 105-120­140 volts or as marked on the terminal plate.

5.6 RESISTOR (FOR TELEPHONE RELAY)

The relay is shipped with resistor in series with tele­phone relay for 125 Vdc ope ration. For 48 V dc oper­ation this resistor is to be shorted.

6.0 INSTALLATION

The relays should be mounted on switchboard p an­els or their equivalent in a location free from dirt, moisture, excessive vibration and heat. Mount the relay vertically by means of the rear mounting stud or studs for the type FT p rojection cas e or by m eans of the four mounting holes on the flange for the semi­flush type FT case. Eith er the stud or the mounting screws may be ut iliz ed fo r gr oundi ng t he rel ay. Exter ­nal toothed washers are p r ovi de d fo r us e i n t he l oca­tions shown on the outline and drilling plan to facilitate making a good electrical connection between the relay case, its mounting screws or studs, and the relay panel. Gr ound Wires are affixe d to the mounting screws or studs as required for poorly grounded or insulating pan el s. Ot her elec tric al
4
CVQ Relay 41-223N
connections may be made directly to the terminals by means of screws for steel panel mounting or to the terminal stud furnished with the relay for thick panel mounting. The termin al stud may be easily remo ved or inserted by locking two n uts on the stud and the n turning the proper nut with a wrench.
For detail information on the FT ca se refer to I.L. 41-
076.

7.0 ADJUSTMENTS & MAINTENANCE

The proper adjustments to insure correct operation of this relay have been made at the factory. Upon receipt of the relay, no adj ust men ts, othe r than th os e covered under Section 5, “ should be required.

7.1 ROUTINE TESTS

The following tests are recommended when the relay is received from the factory. If the relay does not per­form as specified below, t he relay either is not prop­erly calibrated or it contains a defect.
Connect relay per test circuit Figure 6 (page 11). Electrical checks should be made with the relay mounted in its case.
SETTINGS
” (page 4),
left of stationary contact block, the index o n the movement frame will coincide with the “0” mark on the time dial when the stationary contact has moved through a ppr oxi mate ly o ne- ha lf of it s nor ­mal deflection. Therefore, with the stationary contact resting against the backstop, the index mark is offset to the right of the “0” mark by approximately .020”. (For the CV-7 ele ment, the follow on the back contact should be approxi­mately 1/64”.) The pla cement of th e var ious tim e dial positions in line with the index ma rk will give operating times as shown on the time voltage curves of Figure 3 (page 8). For double trip relays, the follow on the stationary contacts should be approximately 1/32”.
(For relay without an identifying “T”)
b) By turning the tim e dial, move the moving con-
tacts until they deflect the stationar y contact to a position where the stationary contact is resting against its backsto p. The index mark lo cated on the movement frame should coincide with the “0” mark on the time dia l. For double trip relays , the follow on the stationary contacts should be approximately 1/64”.
7.1.3.2 Minimum Trip Voltage
7.1.1 Negative Sequence Filter
The filter is adjusted for balance in the factory and no further adjustments or maintenances should be required. The nominal v oltage out put of the fi lters on positive sequence is appro ximately zero. This serves as a convenient check on the balan ce of the filter. If any two input leads to the potential filter should be interchanged, a high v oltage occurs across the out­put terminals of the filter.
7.1.2 Polar Unit
Adjust variable auto-transformer (figure 6, page 11) so that an increasing voltage can be seen on the volt­meter. Note at what v oltage the polar unit ope rates. This voltage should be 10.4 volts ± 0.3 volts.
This corresponds to the 5% sensitivity adjustment. For other sensitivities see Table 1 under calibration.
7.1.3 CV Unit
7.1.3.1 Contact
a) For relays identified with a “T”, located at lower
Set the time dial to position # 6. Alternately appl y tap value voltage plu s 3% and tap value voltage minus 3%. The moving contact should leave the backstop at tap value voltage plus 3% an d sh oul d retur n to th e backstop at tap value voltage minus 3%.
7.1.3.3 Time Curve
Set time dial at #6 dial pos ition. Energiz e termina ls 7 and 8 of relay with 140% of tap value vol tage. The operating time of relay should be 5.9 seconds. The reset time of relay should be 5.7 seconds.
7.1.4 Indicating Contactor Switch (ICS)
Close the main rel ay contacts a nd pass suffi cient dc current through the trip circuit to close the contacts of the ICS. This value of c urrent should not be grea ter than the particular ICS se tting being used. The indi­cator target should drop freely.
The bridging moving co ntact should touch both sta­tionary contacts simultaneously.
5
41-223N CVQ Relay

7.2 ROUTINE MAINTENANCE

All relays should be inspected periodically and the time of operation should be checked at least once every year or at s uch other tim e intervals as may be indicated by exper ience to be suitab le to the pa rticu­lar application.
All contacts should be periodically cleaned. A contact burnisher style 182A836H01 is recommended for this purpose.
contacts is not recommended
The use of abrasive material for cleaning
, because of the dan­ger of embedding small particles in the face of the soft silver contact and thus impairing the contact.

8.0 CALIBRATION

Use the following procedure for calibrating the relay if the relay has been taken apart for repairs, or the adjustments have been disturbed. This procedure should not be used until it is apparent that the relay is not in proper working order (See “Acceptance Check”). Electrical checks should be made with the relay mounted in its case.

8.1 NEGATIVE SEQUENCE VOLTAGE FILTER

A. Apply 120 volts balanced 3 phase voltage 60
hertz to t ermina ls 7, 8, and 9 of t he r elay, maki ng sure that phase A, B, and C of the applied voltage is connected to terminals 7, 8, and 9 respectively.
B. Using a calibrated high resistance voltmeter of
2000 ohms per volt or more, measure the voltage between the tap on auto-transfor mer (middl e ter­minal, upper right-hand reactor, front view) and the tap on the adju stable 2” resistor. If the volt­age is high (40 to 50 volts) the filter is probab ly improperly connected . If properly co nnected, the voltage will be low. Using a low range (ap proxi­mately 5 volts) m ove the adjus table tap until th e voltage reads a minimu m. This value should be less than 1.5 volts.

8.2 POLAR UNIT

8.2.1 Contacts
it just makes with the gage and lock in place. On dou­ble trip relays, a djust the othe r set of cont act gaps t o close simultaneously.
8.2.2 Minimum Trip Voltage
Short out the adjustable resistor in series with the polar element. Using the test circuit of Figure 6, (page 11) adjust the right-hand shunt of the polar unit so that it toggles over with 3.3 ±0.17 volts on the voltmeter. Remove short circuit from the resistor and adjust this resist or so that the p olar unit wil l close its contacts to the left with 10.4 ±0.52 volts on the volt­meter. For other sensitivities as indicated in Table 1, adjust for the voltage shown. Block polar unit con­tacts closed to the r ight before proceedi ng with CV calibration.
Table 1:
Volts on
Voltmeter
10.4
12.5
14.5
16.6
18.7
20.8
% of Line
to Neutral
5 6 7 8 9
10
Polar unit flux paths are s hown in Figure 7 (page 12) with balanced air gaps, perm anent mag net flux flows in two paths, one throug h the front, and one thr ough the rear gaps. This flux produces north and south poles, as shown. By turning the left shunt in, some of the flux is forced th rough the armature, making it a north pole. Thus, redu cing the left-hand r ear gap will produce a force tending to pull the armature to th e right. Similarly, reducing the right-hand gap will make the armature a south pole and produce a fo rce tend­ing to pull the armature to the left.

8.3 CALIBRATION OF POLAR UNIT

If the relay has been dismantled or the calibration has been disturbed, use the following procedure for calibration.
Place a .060 to .070 inch feeler gage between the right-hand pole face and the armature. This gap should be measured n ear the front of the right-han d pole face. Bring up the backstop screw until it just makes with the moving conta ct. Place gage betwee n contact and the stationary contact on the left-hand side of the polar unit, and adju st stationary contacts for 0.046 inches. Br in g u p t he sta tio nar y c ont act until
6
With the permanent magnet removed, see that the moving armature floats in the central area of the air­gap between the poles of the polar unit frame. If nec­essary, loosen the core screw in the center rear of the unit and shift the co r e an d c on tac t as s emb ly until the armature floats. (This can best be done with the polar unit removed from the relay.) Then retighten the core screw and replace the permanent magnet
CVQ Relay 41-223N
with the dimple (north pole) on the magnet to the right when viewed from the front.

9.0 POLAR UNITS - GENERAL

The following mechanical adjustments are given as a guide, and some deviation from them ma y be ne ces ­sary to obtain proper electrical calibration.

9.1 MAGNETIC SHUNT ADJUSTMENT

The sensitivity of the polar u nit is adj usted by me ans of two magnetic, screw-typ e shunt s at th e rear of th e unit, as shown in Figure 7 (page 12). These shunt screws are held in pr oper adjustment by a flat strip spring across the back of the pol ar unit frame, so no locking screws are required. Looking at the relay, front view turning out the right-hand air gap decreases the amount of current required to close the right-hand conta ct. Conversely, drawin g out the left-hand shunt increases the amount of current required to close the right-hand contact, or decreases the amount of current required to close the left-hand contact (with the proper direction of cur­rent flow). Also, if a relay trips to the right at the proper current, the dropout current can be raised by turning in the right- hand shunt. The two shunt-scre w adjustments are not indepe ndent, ho wever , a certai n amount of trimming adju stment of both shunt sc rews is generally necessary to obtain the desired pickup and dropout calibration.
In general, the more the two shunt screws are turne d out, the greater the toggle action will be, and as a result, the lower the dro pout current. For th e tripping units, toggle action is desirabl e, with a dropout cur­rent around 75 percent of the pickup current.
The electrical calibration of the polar unit is also affected by the con tact adjustment as this changes the position of the polar unit armature. Do not change the contact adjustment without rechecking the electri­cal calibration.
9.1.1 CV Unit
9.1.1.1 Contact (see 7.1.3.1)
a) For relays identified with a “T”, located at lower-
left of stationary contact block, the index mark on the movement frame will coincide with the “0” mark on the tim e dial wh en the sta tionar y conta ct has moved throug h approximately one-half of its normal deflection. Therefore, with the stationary contact resting against the backstop, the index mark is offset to the right of the “0” mark by
approximately .020”. (For the type CV-7 relays, the follow on the b ack cont act should b e approxi­mately 1/64”.) . The placem ent of the va rious time dial positions in line with the inde x mark will give operating times as shown on the respective time current curves. For double trip relays, the follow on the stationary contacts should be approxi­mately 1/32” .
b) By turning the tim e dial, move the moving con-
tacts until they deflect the stationar y contact to a position where the stationary contact is resting against its backsto p. The index mark lo cated on the movement frame should coincide with the “0” mark on the time dia l. For double trip relays , the follow on the stationary contacts should be approximately 1/64”.
9.1.1.2 Minimum Trip Voltage
The adjustment of the spring tension in setting the minimum trip voltage value of the relay is most con­veniently made with the damping magnet removed.
With the time dial s et on “0” w ind up th e spiral spring by means of the spring adjuster until approximately 6 3/4 convolutions show. Set the relay on the minimum tap setting and the time dial to position 6.
Adjust the control spring tension so that the moving contact will leave the ba ckstop of the time dial at tap value voltage +1.0% an d will return to the backstop at tap value voltage -1.0%.
Energize terminal 7 and 8 of relay with 140% of tap value voltage. Adju st the permanent magn et keeper until the operating time is 5.9 se conds. Measure the reset time of the disc from the stationary front contact to the stationary back contact. This time should be
5.7 seconds.
9.1.2 Indicating Contactor Switch – Unit (ICS)
Close the main rel ay contacts a nd pass suffi cient dc current through the trip circuit to close the contacts of the ICS. This value of c urrent should not be grea ter than the particular ICS se tting being used. The indi­cator target should drop freely.

10.0 RENEWAL PARTS

Repair work can be done most satisfactorily at the factory. However, interc hangeable parts can be fur­nished to those equipped for doing repair work. When ordering parts, always give the complete nameplate data.
7
41-223N CVQ Relay
Sub 2
Curve 406C883
Figure 3. Typical 60 hertz Time Curves of the CV-7 Unit of the Type CVQ Relay
8
CVQ Relay 41-223N
Figure 4. External Schematic of the type CVQ Relay used in Motor Protection
(For Internal Schematic 188A644 Figure 1)
*Sub 5
762A868
9
41-223N CVQ Relay
10
Sub 5
880A380
Figure 5. External Schematic of the CVQ Relay used for Tripping on Negative Sequence Voltage only
(For Internal Schematic 880A343 Figure 2)
CVQ Relay 41-223N
Sub 1
1482B82
X
A
CB
PHASOR DIAGRAM FOR TEST CONDITION
WITH A-B-C PHASE ROTATION
REPRESENTED BY
TRIANGLE ABC
RELAY TEST VOLTAGE
IS REPRESENTED
SUPPLY VOLTAGE IS 120V 3
(FRONT VIEW)
TYPE CVQ RELAY
10
9
8
7
6
5
4
3
2
1
BY TRIANGLE XBC
2
Figure 6. Test Diagram for Type CVQ Relay
x
VOLTAGE V
3
AX
= 3 TIMES NEGATIVE SEQUENCE
V
AUTO
VARIABLE
TRANSFORMER
A
B
C
120V 3
A-B-C
ROTATION
= V
2
AX
V
V
11
41-223N CVQ Relay
Shunt
N
Permanent Magnet
N
S
Armature
N
S
N
Moving Contact
BALANCED AIR GAPS UNBALANCED AIR GAPS
Figure 7. Polar Unit - permanent magnet flux paths
Polar Unit
S
S
N
Resistor for Filter Calibration
Additional Flux Path
Sub 5
183A062
12
Shunt
Time Dial
Terminal Plate
CV Unit
Front Contact
ICS
Sub 1
9664A46
Figure 8. CVQ Relay without Case (Front View)
CVQ Relay 41-223N
Reserved for Notes
13
41-223N CVQ Relay
Reserved for Notes
14
CVQ Relay 41-223N
Reserved for Notes
15
41-223N CVQ Relay
57D7902
*Sub 17
ABB
Printed in U.S.A
.
Figure 9. Outline and Drilling plan for the Type CVQ Relay in Type FT-31 Case
ABB Automation Inc.
4300 Coral Ridge Drive
Coral Springs Florida 33065
TEL: 954-752-6700
FAX: 954-345-5329
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