LA7K0064 TELEMECANIQUE, LA7K0064 Datasheet - Page 25
LA7K0064
Manufacturer Part Number
LA7K0064
Description
Relay, Overload, Miniature, Accessory, Terminal Block for Separate DIN Rail Mtg.
Manufacturer
TELEMECANIQUE
Datasheet
1.LP1K0910BD.pdf
(28 pages)
Specifications of LA7K0064
Termination
Screw Clamp
04/01
Voltage Drop Caused by the Inrush Current (continued)
What cable c.s.a. is required for the control circuit of an CAD50G7 relay, operated from a distance of 500 meters.
CAD50G7, voltage 120 V, 60 Hz: inrush power: 70 VA.
On the left-hand graph on page 24, point X is at the intersection of the vertical line corresponding to 70 VA and the a 120 V (estimated) voltage curve.
On the right-hand graph on page 24 point Y is at the intersection of the vertical line corresponding to 500 m and the horizontal line passing through point X.
Use the conductor c.s.a. indicated by the curve which passes through point Y, between # 14 and # 16 AWG.
If point Y lies between two c.s.a. curves, choose the larger of the c.s.a. values. In this case # 14 AWG.
Calculating the maximum cable length
The maximum permissible length for acceptable line voltage drop is calculated by the formula:
Where:
L: distance between the contactor and the control device in m, (length of the cable),
U: supply voltage in V,
SA: apparent inrush power drawn by the coil in VA, (Vac) or W (Vdc)
s: conductor c.s.a. in mm
K: factor given in the table below.
a.c. supply
d.c. supply
L
=
U
------ - s.K.
SA
2
2
,
SA in VA
K
Irrespective of the inrush power SA, expressed in W
K = 1.38
©
2001 Schneider Electric All Rights Reserved
20
1.38
40
1.5
100
1.8
Long Distance Control Data
150
2
200
2.15
25