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English
ELMON inductive 74-302
Inductive signal transmission system
10. Error diagnosis
Only the
green
LED may illuminate if the supply voltage has been correctly connected. If one of the
red
LEDs
illuminate, there is an error in the system which can be pinpointed with the aid of the LED.
LED
Error
Error correction
LEDs are not
illuminated
The supply voltage is missing, too
low or has been connected incor-
rectly
Check connections and supply voltage:
- 24 V AC/DC at terminal
24 V AC/DC
or
- 230 V AC at terminals
L1 and N
Tolerance range: ±10%
A single red LED
is illuminated
Contact edge(s) not connected,
connected incorrectly or faulty
- Check the connections of the corresponding
contact edge (squeezed or brittle supply
lines, etc.)
- Check safety contact edge(s)*
One of the contact edge connections
is not being used
Any contact edge connections that are not
being used must be permanently bridged
using one of the supplied 8.2 kΩ resistors
Both of the red
Transmit
LEDs
are illuminated
The transmission line is faulty or has
been installed incorrectly
- Observe the mech. assembly instructions
(ELMON inductive signal transmission sys-
tem)
- Check transmission coil cores for abrasion.
- Check cable loop; make certain that both
transmission coil cores are in the cable loop
- Check cable / gate leaf contact points.
- Check supply voltage**
Contact edge(s) not connected,
connected incorrectly or faulty
- Check the connections of the corresponding
contact edge (squeezed or brittle supply
lines, etc.)
- Check safety contact edge(s)*
* If the error is not related to the system’s wiring, the proper function of the electronics can be tested by
connecting an 8.2 kΩ resistor to each of the SCE inputs on the ELMON inductive 74-302 electronic evalu-
ation system (terminals
Stationary Opening
or
Closing
) and to the travelling coil core (connections
O
and
C
). If the electronics work perfectly after performing the test, the safety contact edges must be checked
using an ohmmeter. To do this, the respective connection on the SCE for the electronic evaluation system
or for the travelling coil core must be disconnected and connected to an ohmmeter.
The resistance must be 8.2 kΩ ±500 Ω when the safety contact edge is inactive and must not exceed 500 Ω
when it is active.
** If both of the LEDs for the travelling SCEs (
Transmit Opening
and
Transmit Closing
) illuminate, there is an
error in the inductive signal transmission system. The most frequent causes of these errors are bad coil
core connections, incorrectly installed cable system components (see ELMON inductive signal transmission
system assembly instructions) or an impermissibly low supply voltage.
The maximum resistance value of the cable loop must not exceed 3 Ω. The resistance value can be measured
by disconnecting the steel cable from the ground terminal and then measuring the resistance between
the end of the steel cable and ground terminal.
