Keri Systems NXT 4x4 - Manual (Page 3)

NXT 4x4
Installation Guide
Page 3 of 4 P/N: 01998-001 Rev. G
Table 2: Reader and 4x4 Cable Options
Connection Type
Total
Run
Length
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.
AWG Suggest AWG Suggest
RS-485 bus

from NXT-2D/-4D

to NXT-4x4 only
up to
500 feet
18 - Data plus
4x4 Power
22 - Data only
Belden
8723
unshielded 18 - Data plus
4x4 Power
22 - Data only
Windy City:
414302-S
West Penn: 244
Tappan:
1880AB4M-CM
RS-485 bus

from NXT-2D/-4D

to NXT-4x4

and NXT Readers
up to
500 feet
18 - Data plus
4x4 Power
22 - Data only
Belden
8723
shielded 18 - Data plus
4x4 Power
22 - Data only
Windy City:
414302-S
West Penn: 244
Tappan:
1880AB4M-CM
RS-485 bus

from NXT-2D/-4D

to NXT Readers only
up to
1,000 feet
22 for Data Belden
8723
shielded 22 for Data Windy City:
416303-S
West Penn: 241
Tappan:
2280AB4M-CM
Table 3: Controller Power, Inputs, and Outputs Cable Requirements
Connection
Total Run
Length
# of
Conductors
Shielded Stranded
Twisted
Pair
AWG
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 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

designated 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 n/a 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 n/a 22 no specific
requirement