Carrier AquaSnap 30RAP011-060 Controls, Start-Up, Operation, Service, And Troubleshooting page 129

To install a BT485 terminator, push the BT485 terminator on to
the BT485 connector located near the BACnet connector.
NOTE: The BT485 terminator has no polarity associated with it.
To order a BT485 terminator, consult Commercial Products i-Vu
Open Control System Master Prices.
MS/TP WIRING RECOMMENDATIONS
Recommendations are shown in Tables C and D. The wire jacket
and UL temperature rating specifications list two acceptable alter-
natives. The Halar specification has a higher temperature rating
1
SPECIFICATION
CABLE
CONDUCTOR
INSULATION
COLOR CODE
TWIST LAY
SHIELDING
JACKET
DC RESISTANCE
CAPACITANCE
CHARACTERISTIC IMPEDANCE
WEIGHT
UL TEMPERATURE RATING
VOLTAGE
LISTING
LEGEND
AWG — American Wire Gage
CL2P — Class 2 Plenum Cable
DC — Direct Current
FEP — Fluorinated Ethylene Polymer
NEC — National Electrical Code
O.D. — Outside Diameter
TC — Tinned Copper
UL — Underwriters Laboratories
APPENDIX D — BACNET COMMUNICATION OPTION (cont)
Fig. E — BT485 Terminator Installation
Table C — MS/TP Wiring Recommendations
Single twisted pair, low capacitance, CL2P, 22 AWG (7x30), TC foam FEP, plenum rated
cable
22 or 24 AWG stranded copper (tin plated)
Foamed FEP 0.015 in. (0.381 mm) wall 0.060 in. (1.524 mm) O.D.
Black/White
2 in. (50.8 mm) lay on pair 6 twists/foot (20 twists/meter) nominal
Aluminum/Mylar shield with 24 AWG TC drain wire
SmokeGard Jacket (SmokeGard PVC) 0.021 in. (0.5334 mm) wall 0.175 in. (4.445 mm) O.D.
Halar Jacket (E-CTFE) 0.010 in. (0.254 mm) wall 0.144 in. (3.6576 mm) O.D.
15.2 Ohms/1000 feet (50 Ohms/km) nominal
12.5 pF/ft (41 pF/meter) nominal conductor to conductor
100 Ohms nominal
12 lb/1000 feet (17.9 kg/km)
SmokeGard 167°F (75°C)
Halar -40 to 302°F (-40 to 150°C)
300 Vac, power limited
UL: NEC CL2P, or better
and a tougher outer jacket than the SmokeGard
it is appropriate for use in applications where the user is concerned
about abrasion. The Halar jacket is also less likely to crack in ex-
tremely low temperatures.
®
NOTE: Use the specified type of wire and cable for maximum sig-
nal integrity.
1. Halar is a egistered trademark of Solvay Plastics.
2. SmokeGard is a trademark of AlphaGary-Mexichem Corp.
RECOMMENDATION
129
specification, and
2