Panasonic GT21

3-12
3.3 Wiring the COM Port
Accessory communication connector/applicable wiring
The communication connector used for the COM port (provided as an accessory with the main unit) has
a screw-tightening type of terminal block. The wiring shown below should be used.
Applicable wiring (twisted wiring)
Size
Conductor cross-section surface area
AWG 28 to 16
0.08 to 1.25 mm
2
Use a special tool to tighten the terminal block of the communication connector.
Use a screwdriver made by us. (Product number: AFP0806). The tightening torque should be 0.22 to 0.3
N· m or less.
When doing RS485 communication using RS422 type
Please use the following cables or equivalent.
Appropriate electrical cables (twisted cables)
Type
Cross-sectional
view
Conductor
Insulator
Cable
diam.
Sample
appropriate
cable
Size
Resist-
ance
(at 20C)
Material
Thick-
ness
Shielded
twisted
pair
1.25 mm
2
(AWG16)
or greater
Max.
16.8
Ω/km
Polye-
thylene
Max.
0.5 mm
Approx.
8.5 mm
Belden 9860
Hitachi Cable,
Ltd. KPEV-
S1.25 mm
2
x
1P
0.5 mm
2
(AWG20)
or greater
Max.
33.4
Ω/km
Polye-
thylene
Max.
0.5 mm
Approx.
7.8 mm
Belden 9207
Hitachi Cable,
Ltd. KPEV-
S0.5 mm
2
x
1P
Note:
 Use shielded twisted pair cables.
 Use only one type of transmission cable. Do not mix more than 1 type.
 When using shielded cable with crossover wiring for the RS485 transmission line, grounded one end.