9.398 NAIS-FP-RTD-Module

This page describes the device driver and the device window for the NAIS-FP-RTD-Module device. This module provides a six-channel PT100/PT1000 temperature sensor interface for the FP0 PLC. Up to three RTD modules may be used with a single FP0 PLC.

For each channel the driver provides individual low/high limits and fault flags which indicate if the temperature value is outside the limits. By default, the temperature sensors are named 'CH-0' .. CH-5' like the RTD module documentation does. The name can be customized, which also changes the name of the fault flags belonging to this channel.

Although 'PT' type temperature sensors are quite accurate without any additional calibration, the device driver provides an individual calibration offset setting for each channel which can be set at the maintenance / setup page.

The NAIS-FP-RTD-Module device may be used together with other NAIS-FP-* devices referring to the same FP0 PLC. See paragraph 'Configuration hints' at the and of this chapter.

Device window pages

The following table shows which device window pages are available with this individual device type. Tool-bar functions not mentioned here are described at the general description of device windows .

• --- Shows the actual temperature values and lets you set individual fault limits.
• --- The faults page.
• --- The device info page.
• --- The maintenance page. The configuration parameters described below are set at this page.

Configuration parameters

At the maintenance page of the device window there are a couple of configuration parameters which must be set to make the software talk to the alarm monitoring input at the PLC.

Defining limits

At the first page of the device window, a low and a high limit value can be set. If the temperature value exceeds one of the limits, a fault is generated and a message is written to the log. To disable the limit checking, set both limit values to zero.

Configuration hints

1. You must set the configuration switches at the RTD module for the type of sensors you use (see the documentation coming with the module).
2. If you want to mix regular I/O modules and a temperature module at one FP0 CPU, you must install the RTD module most far away from the CPU.
3. If you want to use the NAIS-FP0 device together with this driver, set the 'extModules' configuration parameter at the NAIS-FP0 device that the temperature module gets not polled by it.Example:You have an FP0 CPU with one input expansion module and one RTD module. Attach the input expansion to the CPU, the RTD module to the expansion. At the device setup, define the interface to the FP0, choose the NAIS-FPx protocol for it. Attach a NAIS-FP0 device for the I/O ports and a NAIS-FP-RTD-Module device for the measurement module.At the NAIS-FP0 configuration setup set the 'extModules' parameter to '1', at the NAIS-FP-RTD-Module configuration setup set the 'tempModule' parameter to '2'.

Refresh intervals

Due to the principle the of operation of the communication interface between the sat-nms system and the RTD module, there is no fixed refresh cycle time for a particular measurement channel. The driver polls the FP0 every 4 seconds. With each poll, the FP0 replies two of the six channels, in random order.

At average, each channel gets updated every 12 seconds. Due to the random sequence at which the channels get updated, it may happen that a channel gets not updated for a longer time.

Variables defined by this device driver