LC1K0910B7 TELEMECANIQUE, LC1K0910B7 Datasheet - Page 27

• Manufacturer Part Number: LC1K0910B7
• Description: Contactor, Miniature, up to 5 HP at 575/600 VAC 3-Ph., 24 VAC Ctrl., 1 NO Aux.
• Manufacturer: TELEMECANIQUE
• Type: General Dutyr

Specifications of LC1K0910B7

• Current, Rating Max: 9
• Function: Contactor
• Horse Power Rating: 5
• Primary Type: Contactor
• Relay Type: Electro Mechanical
• Dimensions (l × W × H, Mm): 58 × 45 × 57

04/01
Residual Current in the Coil due to Cable Capacitance (continued)
These graphs are for a capacitance, between conductors, of 0.2 F/km. They make it possible to determine whether there is a risk of the contactor
remaining closed due to the power drawn by the coil when sealed and the control circuit voltage, according to the length of the control cable.
Power drawn, sealed in VA
1 24 Vac
2 48 Vac
3 115 Vac
In the zones below the straight lines for 3-wire and 2-wire control respectively, there is a risk of the relay remaining closed.
Examples
What is the maximum length for the control cable of a CAD50 relay, operating on 230 V, with 2-wire control?
- CAD50 relay, voltage 230 V, 60 Hz: power sealed 8 VA.
On the left-hand graph, point A is at the intersection of the vertical line for 8 VA with the a 230 V voltage curve.
On the right-hand graph, point B is at the intersection of the horizontal line with the 2-wire control curve.
The maximum cable length is therefore 300 m.
In the same example, with a 600 m cable, the point lies in the risk zone. A resistor must therefore be connected in parallel with the relay coil.
Using right hand table above, find 600 meter along the bottom and follow up to line B (2 wire control) and then to the left to obtain C value.
Value of this resistance:
Power to be dissipated:
Alternative solution: use a d.c. control supply.
Calculating the Cable Length
The maximum permitted length of control cable to avoid the effects of capacitance is calculated using the formula:
L: distance between the contactor and the control device in km (length of the cable),
S: apparent power, sealed, in VA,
U: control voltage in V,
Co: cable capacitance in F/km. (to be supplied by wire manufacturer for type of wire used)
P
=
0,01
R
100
U
------ -
L
0,1
R
10
2
=
1
=
=
1
--------------------- -
10
455
---------------- -
230
8300
3 –
1
-------------------- -
U
2
C
=
2
=
S
6.5 W
Co
---------------------------- -
10
3 –
1
0.12
5
A
=
©
8 10
8.3k
2001 Schneider Electric All Rights Reserved
4 230 Vac
5 400 Vac
6 690 Vac
2
4
6
1
3
5
50
Cable capacitance in uF
100
0,01
100
0,1
10
1
Length of control cable in m
7 3-wire control
8 2-wire control
100
B
300
Long Distance Control Data
500
1000
7
8
5000 10 000
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