DISCREPANCY SWITCH - Size S0 using S0 Q100 lamp holder (for 9-24 contacts)
The Size S0 Discrepancy Switch using S0 Q100 consist of the following:
1.
The Mounting System.
2.
The Lighting System
3.
Push-in Interlock System
4.
Switch contacts.
5.
Illuminated handle
1. Type S0 Q100
a. Mounting System
i.
Mounting Type EL with round face plate
The
front face plate is round and mounting is by means 2 mounting screws.
Fig. 57 – Type of mounting with round ring
ii. A aluminum plastic square
face plate can be mounted over the round face place. The square plate can be
engraved with legends to show the functions of the various positions. It is
available in round or square:
• Round - 60 mm Ø
• Square - 60 x 60 mm
9E2G C1/F-SG4364 9E2G C1/F-SG4364
b. Push To Turn Interlock System
The Push to Turn Interlock System
is built-in the mounting unit of the switch. The interlocking program is 006
which operate as follows:
Program
|
Normal
Level Handle Rotation
|
Normal
Level Handle Push-in
|
Push-in Level Handle Rotation
|
F
|
From 9 to 12 o'clock
|
At 9 o'clock
At 12 o'clock
|
From 12 to 1 o'clock
From 9 to 8 o'clock
|
2. The Lighting System
a. Lamps Circuit
The size S0 lighting systems
consist of a lamp holder with four socket outlets to accommodate 4 telephone
bulbs type T6.8K (Fig. 48a). Depending on the control voltage, the lamps can be
connected in series/parallel circuit. (Fig. 48b) the advantage of this
arrangement is that should any of the lamps fails, other lamps in the parallel
circuit will still lights up to indicate discrepancy reducing the danger of not
knowing that there is a discrepancy fault due to lamp failures. In the example
shown in Fig. 48b, for a supply voltage of 110V, by having lamps of individual
rating of 60V, and by having the four lamps connected in a series/parallel
network, it is possible to accommodate a supply voltage of 110V.
Fig. 49a For supply voltage 220V DC – 4 lamps of 60V per filament lamp in series circuit
b.
Type of Lamps
Lamp Voltage
|
Max. Power
Per Lamp
|
Reference
|
24V
|
2.0W
|
999 T6.8K/024
|
36V
|
2.0W
|
999 T6.8K/036
|
42V
|
2.0W
|
999 T6.8K/042
|
60V
|
2.0W
|
999 T6.8K/060
|
3. Illuminated Handle
The translucent handle of 28mm
diameter is screws on to the aluminum shaft. The handle will operate the
auxiliary contacts when the handle is Push-in and the switch contacts when
handle is turned. Removal of the handle from the shaft allows access to the lamps
from the front of the panel.
4. The Switch Contact System
The switch contacts operate when
the handle is turn. The switches are suitable for both AC and DC switching.
Types CAD11 with gold plate H-Bridge contact system is especially suitable for:
• Low voltage switching of
electronics, and thermocouple circuits.
• Corrosive environment where
the gold contact prevents oxidation of the contact resistance.
b. AC Switching Capacity
Switch Type
|
CA10
|
CA20
|
CA25
|
CH10 CHR10
|
CH16 CHR16
|
Nominal
Voltage (V)
|
690V
|
690V
|
690V
|
690V
|
690V
|
Nominal
Current (A)
|
20A
|
25A
|
32A
|
20A
|
25A
|
Breaking
Current (A)
|
30A
|
37A
|
48A
|
30A
|
37A
|
Fig 30 – AC Switching Capacity for Discrepancy
Switch S0
c. DC Switching Capacity
In selecting the switch model for
DC switching, it is highly important to determine if the switch would be used
for:
• Making the DC load only.
•
Making and breaking the DC load.
• Breaking the DC load only.
i. DC Utilization Category
The utilization category is determined
by the time constant (L/R) of the load. Hence the more inductive the load is,
the higher will be the time constant. Typical times constant for the various DC
loads are:
Fig 31 - Type of Load and time constant
ii. DC Making Capacity.
The DC Making
capacity is independent from
the value of the DC voltage and is much higher than the DC breaking capacity.
However, it is dependent on the type of DC load (resistive/inductive load). In
selecting a switch for DC making, it is important to consider the following
factors:
• The switch to be used for
making the DC circuits. The breaking of the circuit would be done by other
devices in the circuit e.g. limit switch, contactors etc. Under no
circumstances should the switch selected carry out the breaking of the DC circuit!!!
• The maximum DC voltage should
not exceed the rated insulation voltage (Ui).
• To avoid overheating of the
contacts, the maximum number of operations should not be exceeded.
Type of
|
L/R Time
|
Insulation
|
Rated
Operational
|
Current
|
Load
|
Constant
|
Voltage (Ui)
|
CA10 CA20
|
CA25
|
CH10 CH16
|
||||
CHR10 CHR16
|
||||
Resistive
|
T < 1mS
|
690V
|
20A 25A
|
32A
|
Inductive
|
T = 50mS
|
690V
|
12A 20A
|
25A
|
Fig 32 - DC Making Capacity for Size S0 Discrepancy
Switch
iii. DC Making & Breaking Capacity
When breaking a circuit on DC
Loads, it is important that the voltage across the contacts when the contact
breaks should be below the arc extinguishing voltage Vex. Continuous arcing
across an open contact can damage the contact. The DC breaking capacity at low
DC voltage (below Vex) is generally the same as for AC voltage. However, as the
DC voltage increases, the DC breaking capacity decreases. To increase the
capacity, several contacts are connected in series to attain greater breaking
capacity.
The DC breaking capacity of a switch contact is influenced by:
•
The DC main supply voltage.
• The DC load current
•
The resistively/inductivity of the load which depends on the time
constant T = L/R
.
Rated
Operational Current
|
|||||||
Number of Series
Contacts
|
1
|
2
|
3
|
4
|
CA10
|
CA20
|
CA25
|
CH10
|
CH16
|
||||||
CHR10
|
CHR16
|
||||||
Resistive Load L/R= /< 1 mS
|
24V
|
48V
|
70V
|
95V
|
20A
|
25A
|
32A
|
48V
|
95V
|
140V
|
190V
|
12A
|
20A
|
25A
|
|
60V
|
120V
|
180V
|
240V
|
4.5A
|
7.5A
|
10A
|
|
110V
|
220V
|
330V
|
440v
|
1A
|
1.5A
|
2A
|
|
Inductive Load L/R= 50 mS
|
24V
|
48V
|
70V
|
95V
|
12A
|
20A
|
25A
|
30V
|
60V
|
90V
|
120V
|
5A
|
9A
|
12A
|
|
48V
|
95V
|
140V
|
190V
|
2A
|
3A
|
3A
|
|
60V
|
120V
|
180V
|
240V
|
1A
|
1.5A
|
1.5A
|
|
110V
|
220V
|
330V
|
440v
|
0.4A
|
0.5A
|
0.5A
|
|
Fig. 33 - DC Breaking Capacity for Discrepancy
Switch Size S0
d. Low Voltage Switching - Dry Circuit Rating of Switches
Control circuit device are
designed for use with industrial control equipment where the voltage is
relatively high (110V and above) and the current level are high (normally 0.25A
and above) are generally known as Wet Circuit. At these levels, arcing occurs
whenever the circuit is switch ON or OFF and the arcing burns away the
contaminant, reducing the contact resistance i.e. self-cleaning.
Dry Circuit means no arc occurs
during switching because the current and voltage is too low to generate an arc.
As a result, any contaminant on the contact surface cannot be removed. For such
applications, self-cleaning contacts and non-corroding contact is recommended
for use. It is important that the Dry Circuit ratings should not be exceeded
because the gold plating may be burnt off.
In selecting the switch model for
low voltage switching, the Dry Circuit Rating should not be exceeded. The Dry
Circuit Rating refers to the relationship between the supply voltage and load
current. If the value exceeds, arcing may occur which would remove the layer of
gold on the contact.
Minimum Switch Dry Circuit Rating Contact Contact
|
||||||
Voltage
|
Type
|
Voltage
|
AC21A
|
DC21B
|
Type
|
Material
|
30mV
|
CAD11
|
1V
6V
12V
24V
48V
|
6A
3
2A
1A
0.8A
|
4A
2.5A
1.5
0.8A
0.3A
|
H-Bridge
|
Gold alloy
|
1V
|
CH11/CHR11
|
1V
6V
12V
24V
48V
|
6A
3
2A
1A
0.8A
|
4A
2.5A
1.5A
0.8A
0.3A
|
H-Bridge
|
Gold alloy
|
6V
|
CAD12
|
6V
12V
24V
48V
|
6A
6A
5A
4A
|
4A
3A
2.2A
1.2A
|
H-Bridge
|
Silver alloy
|
6V
|
CAD12
|
6V
12V
24V
|
6A
6A
5A
|
4A
3A
2.2A
|
H-Bridge
|
Silver alloy
|
48V
|
4A
|
1.2A
|
||||
Fig. 34 - Dry Circuit Rating for Discrepancy Switch
Size S0
Optional Extras
a. Lost Motion Contacts
This type of switch is divided into two parts. The
front portion contains the regular switch contacts, which is operated by
turning the handle. The rear portion of the switch can accommodate the Lost
Motion Contacts. Using the slip clutch M200 in which two camshafts can be
coupled in such a way that the secondary camshaft will operate only after the
primary camshaft has been moved over a pre-determined angle does this. The slip
clutch is housed in a blank switch stage.
b. Position Indicator
The position
indictor provides a visual indication of the current switch position. The
features are as follows:
•
Brushed aluminum plate with black lettering. Other color combination
available on request.
TYPICAL REQUIREMENT
When the handle
of a discrepancy switch is turn 90o, the mimic
diagram of the control panel placed in the Control room will immediately
indicate any circuit interruptions. At the same time, the switch contact
connect in series with the circuit breaker limit switch will operate the lamp
inside the handle. The lamp will light up only when there is a discrepancy
between switch position and the actual position of the circuit breaker, which
is in a remote location. For example, if the handle is in the CLOSED position
(A) and the circuit breaker is also CLOSE, the lamp in the discrepancy switch
will not light up because there is no discrepancy. However, if the breaker TRIP
because of a fault condition, the circuit breaker limit switch will close the
lamp circuit and the lamp in the discrepancy switch handle will be energize
because the circuit breaker is now open whereas the discrepancy switch in the
Control Room still remains in the CLOSE position. The lamp in the Discrepancy
Switch lights up and an audible alarm advise the operator in the Control room
of the discrepancy between the actual circuit breaker condition and the switch
condition. The operator will then turn the switch to TRIP (position E) to reset
the discrepancy condition. Two lost motion contacts are required as well as two auxiliary (1NO+1NC)
contacts which operates
when the handle is Push-in.
Fig. 41 shows
a typical application of a discrepancy switch and the contact arrangement
required for this particular application. Contact rating is 10A and voltage
supply is 110 VDC. Two auxiliary contacts (1NO + 1NC) for Signaling will
operate when the handle is Push-in. Two Lost Motion contacts to be provided to
light up the lamp when discrepancy arises.
ORDERING PROCEDURE for Discrepancy Switch Size S0
When ordering a Size S0
discrepancy switch, the following information is required:
• Switch Type - 10A / 110VDC
In the discrepancy switch
circuit, under normal condition, no current flows to the breaker coil. When a
discrepancy arises, the breaker motor drive will turn the breaker from CLOSE to
TRIP resulting in a discrepancy. At the TRIP position no current flows. Hence,
the discrepancy switch is only used for making the circuit to the coil but not
for breaking the circuit. Hence the DC making chart in Fig 31 can be used for
selecting the correct switch i.e. Type CA10.
• Mounting Type
Mounting required will be *E
as according to Fig. 57.
• Coding for Control and Indicator Device/ Push-pull Interlock , the coding is S0 Q100/SGX1301 and S0 V130/SGX1302
•
Switch Configuration
The switching configuration is
as shown in Fig 41.
The switch should be given a
special switch reference CA10 SGxxxx2
• Lamp Rating
The voltage of the power
supply is 110VDC.
The reference code for a filament
lamp is S0 Q100/SGX1498 (Fig. 48b)
• Lost Motion contact
A slip clutch is required to
operate two lost motion contacts.
•
 |
Position Indicator – 9E2G
C1/F-SG4364 (Fig. 39) Hence the ordering code is as follows:
MÃ HÀNG THÔNG DỤNG:
Khóa điều khiển máy căt: CA10-SGE108*FT
Dòng điều khiển: 20A
Điện áp: 690V
Bóng đèn: 110 VDC
Bóngđèn :220-480VAC
Khóa điều khiển dao cách ly: CA10-SGE109*FT
Dòng điều khiển: 20A
Điện áp: 690V
Bóng đèn: 110 VDC
Bóngđèn :220-480VAC
Dòng điều khiển: 20A
Điện áp: 690V
Bóng đèn: 110 VDC
Bóngđèn :220-480VAC
Ms. Hiền
HP: 0985147560 -
0901 40 77 59
Skype: hien042015
