Manual

NXT 2-D/4-D Controller
Installation Guide
Page 5 of 6 P/N: 01997-001 Rev. I
Table 2: Reader and 4x4 Cable Options
Connection Type
Total Run
Length
Minimum
AW G
Shielded,
Stranded,
2 Twisted-
Pair
a
a. Keri recommends this cable type for best system performance.
CAT-5
b
b. Keri’s preferred low-cost option. Keri has no suggested vendor for this type of cable.
Shielded,
Stranded,
4-Conductor
c
c. Use care when routing this type of cable as it can make the system more susceptible to EMI.
Suggest Suggest
RS-485 bus 
from NXT-2D/-4D 
to NXT-4x4 only
up to
500 feet
18 - Power
22 - Data
Belden
8723
shielded Windy City:
414302-S
Tappan:
1880AB4M-CM
RS-485 bus 
from NXT-2D/-4D 
to NXT-4x4 
and NXT Readers
up to
500 feet
18 - Power
22 - Data
Belden
8723
shielded Windy City:
414302-S
Tappan:
1880AB4M-CM
RS-485 bus 
from NXT-2D/-4D 
to NXT Readers only
up to
1,000 feet
18 - Power
22 - Data
Belden
8723
shielded Windy City:
416303-S
Tappan:
2280AB4M-CM
Table 3: Controller Power, Inputs, and Outputs Cable Requirements
Connection
Total Run
Length
# of
Conductors
Shielded Stranded AW G
Belden
Equivalent
controller power
250 feet
a
a. To meet CE and C-tick regulations, the length of the controller power line can be no longer than 
3 Meters (9.85 feet).
2 N Y 18 8461
earth ground shortest
path
b
b. Use the shortest possible path from earth ground point to PCB. Connect the earth ground only to the desig-
nated pin on the terminal block. This is important as all transient protection for the unit is made through this
earth ground connection. For unit protection, the earth ground connection should always be made first.
1 N N 18 no specific
requirement
inputs and outputs
c
c. Values listed are minimums. Individual input and output devices may have more specific 
requirements.
500 feet 2 N Y 22 no specific
requirement