Surge Protector Wiring - Danfoss ECL Comfort 296 Service Manual

Service guide
Site 1
Common signal shorted with PE (protective earth)
BUT common signal must be connected to earth ONLY ONE POINT (section 5 point 5).
So use "PT 1X2 +F-BE" and avoid "PT 1x2-BE".

8.2 Surge protector wiring

The correct wiring is equally important to get the best "surge protec-
tion in the network level.
The "gas discharge tubes" (between pin 7, 6 to 9 in the juxtaposed
example) is capable of handling higher surge current, but this device
is slow responding.
The "transils" (between pin 8 to 12 and 10) are capable of handling
low surge current, but very fast responding. These two sets of com-
ponents (gas discharge tubes and transils) are separated by a resistor
which forces the surge to be first suppressed by the gas discharge
tube and the residue will be suppressed by the transil in the proper
installation ("field cables" to "gas discharge connection points" and
"electronics to be protected" are connected to "transil connection
points").
Refer the juxtaposed drawing for example.
• Odd numbered connection of PT 1X2+F-BE meant for outer filed
cables (both IN and OUT cable wires of field cable)
• Even numbered connection of PT 1X2+F-BE meant for repeater/
ECLs wires (both IN and OUT cable wires of ECLs / repeaters)
"Base part and surge protector data sheets must be referred before
making connection".
VI.LV.H1.02
ECL 296 / ECL 310 Modbus
Cable to next house
PT 1x2-BE
Site 2
Common signal shorted with PE (protective earth)
PT 3-PB-ST and PT 1X2+F-BE logical drawing:
3-wire, PROFIBUS (up to 12 MHz)
Total width 17.7 mm
PT 1x2-BE
© Danfoss | 2017.06 | 11