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.

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Honeywell W7752D specifications Overview, Plan the System, Determine Other Bus Devices Required, Step No Description

W7752D specifications

The Honeywell W7752D is a versatile and advanced electronic gas combination control designed primarily for use in commercial heating systems. This product stands out for its ability to manage both gas ignition and safety functions, which are critical for maintaining the efficiency and safety of heating appliances. Its robust construction and advanced features make it a popular choice for HVAC professionals and service technicians.

One of the main features of the W7752D is its integration of multiple functions in a single device. It serves as both an automatic gas ignition control and a safety shut-off valve, which simplifies installation and reduces the need for additional components. This integrated design not only enhances reliability but also streamlines maintenance procedures.

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