Honeywell W7752D specifications Overview, Plan the System, Determine Other Bus Devices Required

EXCEL 10 FCU CONTROLLER LNS PLUG-INS USER GUIDE

APPLICATION STEPS

Overview

Steps one through seven (see Table 8) address con- siderations for engineering an Excel 10 FCU System. These steps are guidelines intended to aid understanding of the pro- duct I/O options, bus arrangement choices, configuration options and the Excel 10 FCU Controllers’ role in the overall EXCEL 5000® System architecture.

	Table 8. Application steps
Step No.	Description
1	Plan the System
2	Determine Other Bus Devices Required
3	Lay Out Communication and Power Wiring
4	Prepare Wiring Diagrams
5	Order Equipment
6	Configure Controllers
7	Troubleshooting

Step 1. Plan the System

Plan the use of the FCU Controllers according to the job requirements. Determine the location, functionality and sensor or actuator usage. Verify the sales estimate of the number of FCU Controllers and wall modules required for each model type. Also check the number and type of output actuators and other accessories required.

When planning the system layout, consider potential ex- pansion possibilities to allow for future growth. Planning is very important to be prepared for adding HVAC systems and controllers in future projects.

engineering process to ensure their implementation when configuring the controllers. (See section "Step 6. Configure Controllers" [page 25] for information on the various Excel 10 FCU Controller parameters and on Excel 10 FCU Controller point mapping.)

Step 2. Determine Other Bus Devices Required

A max. of 62 nodes can communicate on a single LONWORKS segment. If more nodes are required, a router is necessary. Using a router allows up to 125 nodes, divided between two LONWORKS segments. The router accounts for two of these nodes (one node on each side of the router). Table 9 summarizes the LONWORKS segment configuration rules.

Table 9. LonWorks configuration rules and number of

device nodes

One LONWORKS Segment	Max. No. of Nodes = 62
(Example)
Max. no. of Excel 10	60 nodes (T7460/T7560 wall
Controllers	modules are not LONWORKS
	nodes)
Total	62 nodes
Two LONWORKS Segments	Max. No. of Nodes = 125
(Example)
Max. no. of Excel 10	60 nodes (T7460/T7560 wall
Controllers in segment	modules are not LONWORKS
number one	nodes)
Max. no. of Excel 10	60 nodes (T7460/T7560 wall
Controllers in segment	modules are not LONWORKS
number two	nodes)
Total	125 nodes

notebook PC

using an LNS tool

shielded interface cable

RS-232

serial

port

SLTA

Excel 10

FCU

controller

LonWorks

port

The max. length of an FTT LONWORKS segment is 4600 ft (1400 m) for a daisy chain configuration or 1650 ft (500 m) total wire length and (400 m) node-to-node for any other type of configuration.

NOTE: In the case of FTT LONWORKS segments, the distance from each transceiver to all other trans- ceivers and to the termination must not exceed the max. node-to-node distance. If multiple paths exist, the longest one should be used for the calculation.

If longer runs are required, add a router in order to partition the system into two segments.

Fig. 12. Connecting the portable operator terminal to the

LONWORKS network

The LONWORKS communication loop between controllers must be laid out according to the guidelines applicable for that topology. FCU Controllers use FTT technology which allows daisy chain, star, loop or combinations of these bus configurations. See section "Step 3. Lay Out Communications and Power Wiring" (page 18) for more information on bus wiring layout, and see Fig. 13, Fig. 14, and Fig. 15 in section "Step 4. Prepare Wiring Diagrams" (page 19) for wiring details.

It is important to understand the interrelationships between FCU Controllers on the LONWORKS network early in the job

In addition, all LONWORKS segments require the installation of a Bus Termination Module. For an FTT LONWORKS segment, one or two Termination Modules may be required depending upon the bus configuration. See section "Step 3. Lay Out Communications and Power Wiring" (page 18) and the LONWORKS Termination Module subsection in section "Step 4. Prepare Wiring Diagrams" (page 19) for more details.

17 EN2B-0285GE51 R0909