General Installation
Installation Manual 47
2.3.2 Extension Connection
KX-TD816
Extension jacks 1 through 8 are for all kinds of telephones.
Maximum Cabling Distance
The maximum length of the extension line cord (twisted cable) which connects the system and
the extension is as follows:
Telephone Wiring
2 or 4-conductor wiring is required for each extension as listed below. There are four pins for
possible connection: "T", "R", "D1" and "D2".
T:Tip
R:Ring
D1:Low
D2:High
Diameter of the line Max. length
Single Line Telephone 22 AWG
24 AWG
26 AWG
1798 m (5900 feet)
1128 m (3700 feet)
698 m (2290 feet)
Proprietary Telephone /
DSS Console
22 AWG
24 AWG
26 AWG
360 m (1180 feet)
229 m (750 feet)
140 m (460 feet)
Telephone Wiring
Single line telephones 1 pair wire (T, R)
Digital proprietary telephone
(e.g., KX-T7436, KX-T7235)
1 pair wire (D1, D2) or
2 pair wire (D1, D2, T, R) for eXtra Device Port
Analog proprietary telephone
(e.g., KX-T7030, KX-T7130)
2 pair wire (D1, D2, T, R)
DSS console
(e.g., KX-T7440, KX-T7240)
1 pair wire (D1, D2)
