TC-Double (+)
On glass heat exchangers the correct position of the seal is im-
portant when connecting the gas lines (see image). The seal
consists of a silicone ring with a PTFE sleeve. The PTFE side
must face the glass thread.
Glass
PTFE
4.3 Electrical connections
The operator must install an external separator for the device
which is clearly assigned to this device.
This separator
• must be located near the device,
• must be easy for the operator to reach,
• must comply with IEC 60947-1 and IEC 60947-3,
• must separate all live conductors and the status output,
and
• must not be attached to the power feed.
WARNING
Hazardous electrical voltage
The device must be installed by trained staff only.
CAUTION
Wrong mains voltage
Wrong mains voltage may damage the device.
Regard the correct mains voltage as given on the type plate.
WARNING
High voltage
Damage to the device in case of insulation testing
Do not proceed insulation tests with high voltage to the
device as a whole!
Electric strength test
This device is equipped with extensive EMC protection. The
necessary tests were carried out at the factory (test voltage
2.1 kV or 2.55 kV DC depending on approval).
If you wish to check the electric strength again yourself, you
can do so on the entire unit. Only test the device with the spe-
cified values using direct current voltage. Testing the electric
strength with alternating current voltage will damage elec-
tronic components. The recommended voltage in this case is
2.1 kV DC, 2 s. Disconnect all supply lines from the device be-
fore testing. Power can be supplied via the mains connection.
BX440021 ◦ 09/2021
Plug connection
This device has one EN 175301-803 plug each for the power
supply and the signal output. If the lead is connected cor-
rectly, these cannot be confused. Therefore please be sure to
correctly reassemble the plugs after connecting the wires. Be-
low you will find the pin assignments, with the numbers cor-
responding to those on the plugs:
The supply line cross-sections must be suitable for the rated
current. Use a maximum line cross-section of 1.5 mm²
(AWG 16) and a cable diameter of 8 - 10 mm (0.31 - 0.39 inch).
Shielded signal lines are required to connect the analog out-
put or the digital interface.
Plug numbering
Alarm contact S2
Digital output S4
1 - not used
2 - RS485 A
3 - GND/Common
4 - RS485 B
5 - Shielding
The clamping areas for S1 and S2 are 8 - 10 mm (0.31 – 0.39
inches) in diameter.
4.4 Signal outputs
The device has various status signals. The maximum switch-
ing power of the alarm outputs is 250 V AC/150 V DC, 2 A, 50
VA, each.
An alarm is triggered by the alarm contact/status output (S2)
if the temperature in block 1 is outside the specified limits. It
does not indicate if the alarm was triggered due to excess
temperature or insufficient temperature.
Electric supply S1
Analog output S3
1 - not assigned
2 - not assigned
3 - GND
4 - 4-20 mA out
5 - shield
Bühler Technologies GmbH
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