ero electronic LFS Manuel De Service page 8

B.1) LOGIC INPUT B.1) LOGIC INPUT B.1) LOGIC INPUT B.1) LOGIC INPUT B.1) LOGIC INPUT
This instrument can use the input "IN CT/SP-
SP2" (connections 14 and 15) as current
transformer input or logic input.
Safety note:
1) Do not run logic input wiring together with
power cables.
2) Use an external dry contact capable of
switching 0.5 mA, 5 V DC.
3) The instrument needs 100 ms to recognize a
contact status variation.
4) The logic inputs are NOT NOT NOT NOT NOT isolated by the
measuring input.
5) This feature excludes the current transformer
input.
IN CT/SP-SP2
14
15
Fig. 7 - LOGIC INPUT WIRING
When the logic input is selected, it is used to
switch, by an external contact, from main set
point to second set point and viceversa.
logic input op. set point
open SP
close SP2
LFS-1-CC.P65 5
B.2) CURRENT TRANSFORMER INPUT B.2) CURRENT TRANSFORMER INPUT B.2) CURRENT TRANSFORMER INPUT B.2) CURRENT TRANSFORMER INPUT B.2) CURRENT TRANSFORMER INPUT
This instrument can use the input "IN CT/SP-
SP2" (connections 14 and 15) as current
transformer input or logic input.
Safety note:
1) Do not run current transformer input wiring
together with AC power cables.
2) The minimum active period to perform this
measurement is equal to 400 ms.
3) This feature excludes the logic input function.
4) The input impedance is equal to 10 Ω.
14
Current
transformer
15
Load
Fig. 8 - CURRENT TRANSFORMER INPUT
WIRING
This input allows to measure and display the
current running in the load driven by the
OUTPUT1 during the ON and OFF period of the
OUT 1 cycle time. By this feature it is also
available the "OUT 1 failure detection" function
(see page 20).
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13/07/2004, 14:40