Carrier 48P2, P5030-100, P3, P4 Optional UPC Open Installation, MS/TP Wiring Recommendations

c.Secure the black (–) wire to CCN screw terminal – on the COMM board.

d.Secure shield wire to CCN screw terminal SHIELD on the COMM board.

IMPORTANT: A shorted CCN bus cable will prevent some routines from running and may prevent unit from starting. If abnormal conditions occur, unplug the connec- tor. If conditions return to normal, check CCN connector, and run new cable if necessary. A short in one section of the bus can cause problems with all system elements on the bus.

Optional UPC Open Installation

WIRING THE UPC OPEN TO THE MS/TP NET- WORK — The UPC Open controller communicates using BACnet on an MS/TP network segment communications at 9600 bps, 19.2 kbps, 38.4 kbps, or 76.8 kbps.

Wire the controllers on an MS/TP network segment in a dai- sy-chain configuration. Wire specifications for the cable are 22 AWG (American Wire Gage) or 24 AWG, low-capacitance, twisted, stranded, shielded copper wire. The maximum length is 2000 ft.

Install a BT485 terminator on the first and last controller on a network segment to add bias and prevent signal distortions due to echoing. See Fig. 85-87.

To wire the UPC Open controller to the BAS network:

1.Pull the screw terminal connector from the controller's BAS Port.

2.Check the communications wiring for shorts and grounds.

3.Connect the communications wiring to the BAS port’s screw terminals labeled Net +, Net -, and Shield.

NOTE: Use the same polarity throughout the network segment.

4.Insert the power screw terminal connector into the UPC Open controller's power terminals if they are not current- ly connected.

5.Verify communication with the network by viewing a module status report. To perform a module status report

using the BACview keypad/display unit, press and hold the “FN” key then press the “.” Key.

To install a BT485 terminator, push the BT485 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 — Recommen- dations are shown in Tables 29 and 30. The wire jacket and UL temperature rating specifications list two acceptable alterna- tives. The Halar specification has a higher temperature rating and a tougher outer jacket than the SmokeGard specification, 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 signal integrity.

Smoke Control Modes — Rooftop units can be used for aid in building smoke control in the event of a building fire. The available functions include: Fire Shutdown, Pressuriza- tion, Evacuation, and Smoke Purge. These functions are enhanced when multiple rooftop units are used to zone a build- ing. See Table 31 and Fig. 82 and 83.

FIRE SHUTDOWN — Fire Shutdown mode terminates all unit operation (cooling, heating, supply fan, and power exhaust). This mode prevents recirculation of contaminated air back into the space. The mode will not allow admission into the space of unsuitable outside air. See Fig. 82 for wiring.

PRESSURIZATION — Pressurization mode is intended to keep smoke out of a zone. The factory-installed optional econ- omizer is required for this function. Pressurization is accom- plished by the following:

•opening the economizer (option)

•running the supply fan (optional inlet guide vanes open or optional VFD at normal duct static pressure set point)

•closing the power exhaust dampers (if installed as option or accessory)

•shutting off the power exhaust fans (if installed as option or accessory)

		Table 29 — MS/TP Wiring Recommendations
	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
	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

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