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APPENDIX E — UPC OPEN CONTROLLER (cont)
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 H and I. The wire jack-
et and UL temperature rating specifications list two acceptable
alternatives. The Halar
1
specification has a higher temperature
rating and a tougher outer jacket than the SmokeGard
2
specifi-
cation, and it is appropriate for use in applications where the
user is concerned about abrasion. The Halar jacket is also less
likely to crack in extremely low temperatures.
NOTE: Use the specified type of wire and cable for maximum sig-
nal integrity.
Table H — MS/TP Wiring Recommendations
LEGEND
Fig. K — BT485 Terminator Installation
1. Halar is a registered trademark of Solvay Plastics.
2. SmokeGard is a trademark of AlphaGary-Mexichem Corp.
SPECIFICATION
RECOMMMENDATION
Cable
Single twisted pair, low capacitance, CL2P, 22 AWG (7x30), TC foam FEP, plenum rated cable
Conductor
22 or 24 AWG stranded copper (tin plated)
Insulation
Foamed FEP 0.015 in. (0.381 mm) wall 0.060 in. (1.524 mm) O.D.
Color code
Black/White
Twist Lay
2 in. (50.8 mm) lay on pair 6 twists/foot (20 twists/meter) nominal
Shielding
Aluminum/Mylar shield with 24 AWG TC drain wire
Jacket
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.
DC resistance
15.2 Ohms/1000 feet (50 Ohms/km) nominal
Capacitance
12.5 pF/ft (41 pF/meter) nominal conductor to conductor
Characteristic impedance
100 Ohms nominal
Weight
12 lb/1000 feet (17.9 kg/km)
UL Temperature Rating
SmokeGard 167°F (75°C)
Halar -40 to 302°F (-40 to 150°C)
Voltage
300 Vac, power limited
Listing
UL: NEC CL2P, or better
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
Summary of Contents for WEATHERMAKER 48A2020
Page 112: ...112 Fig 20 Typical Main Control Box Wiring Schematic 48 50A Units ...
Page 113: ...113 Fig 21 Typical Auxiliary Control Box Wiring Schematic ...
Page 114: ...114 Fig 22 Typical 2 Stage Gas Heat Wiring Schematic Size 060 Units Shown ...
Page 115: ...115 Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown TO NEXT PAGE ...
Page 116: ...116 Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown cont ...
Page 117: ...117 Fig 24 Typical Electric Heat Control Schematic 50 Series Size 060 Units Shown ...
Page 118: ...118 Fig 25 Typical Controls Option Wiring Schematic SW1 SW2 OR DEHUMIDIFY SWITCH ...
Page 119: ...119 Fig 26 Typical Power Schematic 48 50A2 A3 A4 A5 060 Unit Shown ...
Page 120: ...120 Fig 27 Typical Power Schematic of Greenspeed Low Ambient Option 48 50A 060 Unit Shown ...
Page 121: ...121 Fig 28 Typical Small Chassis Component Location Size 020 035 Units ...
Page 122: ...122 Fig 29 Typical Large Chassis Component Locations Size 040 060 Units ...
Page 185: ...185 APPENDIX C VFD INFORMATION cont Fig F Internal Enclosure Fan Replacement A48 7716 ...