EXCEL 10 FCU CONTROLLER LNS PLUG-INS USER GUIDE

PID

The options for configuring PID parameters with defaults are shown in the following table. See section "Configurations" on page 12 for more information about parameters.

Table 23. FCU Controller PID configuration options

function

configuration options

default

cooling proportional gain1

P control: 2.25 to 180 DDF (1.25 to 100 K) (0 = disable)

36 DDF (20 K)

PI control: 3.6 to 180 DDF (2 to 100 K) (0 = disable)

 

 

heating proportional gain1

P control: 2.25 to 180 DDF (1.25 to 100 K) (0 = disable)

36 DDF (20 K)

PI control: 3.6 to 180 DDF (2 to 100 K) (0 = disable)

 

 

cooling reset time

10 to 3200 seconds (0 = disable)

250 s

heating reset time

10 to 3200 seconds (0 = disable)

250 s

 

 

 

cooling derivative time

1 to 3200 seconds (0 = disable)

0

heating derivative time

1 to 3200 seconds (0 = disable)

0

cooling boost temperature

0.9 to 18 DDF (0.5 to 10 K) (0 = disable)

1.8 DDF (1 K)

 

 

 

heating boost temperature

0.9 to 18 DDF (0.5 to 10 K) (0 = disable)

1.8 DDF (1 K)

Notes:

1. Prior to version 1.0.3, the minimum proportional gain was 7.2 DDF (4 K) for all control algorithms.

Commissioning

Commissioning is the process of writing the LONWORKS® addresses, the binding information and the configuration to the Excel 10 Controller. Any LNS tool can be used to perform these activities, as described in Appendix B.

ID Number

Each Excel 10 FCU Controller is shipped with an internal Identification Number from the factory called the Neuron ID®. The ID number can either be manually entered or it can be received from the network. Pressing the bypass push-button on the Excel 10 wall module for an FCU Controller when it is in Service Mode causes it to broadcast a service message containing its Neuron ID number. This ID number is on a removable sticker on the controller housing and can be typed in manually.

Step 7. Troubleshooting

Troubleshooting Excel 10 FCU Controllers and Wall Modules

In addition to the following information, refer to the various Checkout and Test manuals for these products. See Applicable Literature section for form numbers.

Alarms

When an Excel 10 FCU Controller has an alarm condition, it reports it to the central node on the LonWorks network via the variable nvoAlarm. See Table 24. The information contained in nvoAlarm is:

Subnet Number: The LonWorks subnet that contains the Excel 10 FCU Controller node that has the alarm condition.

Node Number: The Excel 10 FCU Controller node that has the alarm condition.

Alarm Type: The specific alarm being issued and return to normal. An Excel 10 FCU Controller can provide the alarm types listed in Table 24.

All current alarms are contained in a variable called nvoAlarmStatus which is composed of three bytes (nvoAlarmStatus.alarm_bit[n] with n = 0 through 2) with a bit corresponding to each of the alarms listed in Table 24. The coding is ordered in that the least significant bit of nvoAlarmStatus.alarm_bit[0] corresponding to alarm type 1, the most significant bit corresponding to alarm type 8, the least significant bit of nvoAlarmStatus.alarm_bit[1] corresponding to alarm type 9, and so on. Even alarms that are suppressed in nvoAlarm (see below) are contained in nvoAlarmStatus.

Also, the Excel 10 FCU Controller variables, nvoAlarmLog.type[n], where n is 0 through 4, that store the last five alarms to occur in the controller, are available. Certain alarm conditions are suppressed conditionally as follows:

If an input network variable with failure detect is bound to the same node as nvoAlarm, then nvoAlarm and nvoAlarmLog do not report the related FCU Controller variable receive failure error and its associated return to normal. Suppression only occurs when the nvoAlarm is bound to only one node using LonWorks subnet/node addressing and only after the input variable has actually received a network variable from the node since the latest application restart (or power-up condition

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Honeywell W7752D Commissioning, ID Number, Troubleshooting Excel 10 FCU Controllers and Wall Modules, Alarms

W7752D specifications

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