13
T412 SERIES
MEASUREMENT SIGNAL TRANSFER
All the cables transferring the measurement signals must:
be separated from the power cables
be shielded cables with twisted conductors
have at least 0.5 mm² section
be twisted with a 60mm pitch maximum
be firmly fixed inside the terminal boxes
have tinned or silvered conductors
NOTE: to install the sensors and signal transferring cable correctly, read the sensor and SCS/Sensor installation rule
manual.
All T series control units have linearity of the sensor signal, with a maximum error of 1% of full scale value.
TEMPERATURE SENSOR DIAGNOSTICS (only control unit with Pt100 sensors)
In case of failure or exceeded minimum/maximum full scale value of one of the thermometric sensors installed on the
machine to be protected, the FAULT relay switches immediately with the relative warning of faulty sensor on the
corresponding channel.
Fcc highlights that the sensor is short-circuited or that the minimum full scale value of the unit has been
exceeded.
Foc highlights that the sensor is open or that the maximum full scale value of the unit has been exceeded.
To eliminate the message and reset FAULT switching, it is necessary to check the Pt100/TCK connections and replace
the faulty sensor (if any). If the minimum/maximum full scale value has been reached, check that the ambient conditions
match the control unit reading.
Note: exceeding the minimum/maximum full scale value can be caused by interference on the sensor lines; in this case
we recommend that you check:
the correct installation of the sensors and above all of the extension cable (as stated in the paragraph MEASUREMENT
SIGNAL TRANSFER)
the activation of the FCD function of the control unit (as stated in the FCD FUNCTION NOTES on page 15).
TEMPERATURE DIAGNOSTICS
When the temperature sensor detects the temperature is 1°C higher than the value set as pre-alarm limit, relay L1
switches after about 4".
The same happens when the trip temperature threshold is exceeded and the L2 relay switches.
As soon as the detected temperature goes 1°C below the limit set for the L1 and L2 relays switching, these relays
deenergize and the relative LEDs switch off.
If the FLAG function has been programmed, the L1 and/or L2 relays shall remain energised from the moment
the type of alarm is recognized to the following RESET.
L1 AND L2 RELAY RESET (FLAG)
To reset the alarm relays (if the HOLD function is ON), just press the RESET key.
PROGRAMMED DATA DIAGNOSTICS
In case of failure of the internal memory or alteration of the programmed data, at start-up
Ech
is displayed
with the relative warning of the Fault contact.
In this case, for safety reasons, the default parameters are loaded automatically (see the programming table on pages
11 and 12 according to the model purchased).
Eliminate the
Ech
message by pressing RESET and enter the desired values.
Finally switch the unit off and back on to check the memory works correctly, if it is damaged
Ech
will be displayed again
(send the control unit to TECSYSTEM srl for repair).
NOTE:
the use of cables not complying with the above might cause reading anomalies. It is always important to take
into account that any interference on the signal lines might cause anomalies on the inputs or the sensors themselves.
