Spider usage for temperature acquisition

[Sergio Bertana]

A customer asked us if it is possible to use the Spider to manage temperature acquisition using a proprietary RS485 network. The Spider was born to be connected to devices Poseidon to manage temperature sensors on Industrial bus (RS485). But it is also possible using a simple serial protocol to manage the Spider from any product that can communicate on the RS485 line.
 
Let's see how to manage it from a PC using a terminal emulation program and an RS485 connection. As a terminal emulation program it is possible to download the program from the site Toolly, for the connection in RS485 it is possible to use our converters from RS232 to RS485 or from USB to RS232 / 485.
 
The device must be connected to the RS485 line using the 4 (B-) and 5 (A +) pins of the RS45 input RJ485 connector and set the serial communication parameters to 9600, n, 8, 1. Warning! The commands must be sent in a maximum time of 3 Sec, care must be taken when they are sent from the keyboard, it is preferable to use the macros from the terminal program.
 
In order to operate in RS485 multidrop networks, each device has its own address that must be set by the relative jumpers on the module.
 
The command is: T I, example TAI
If the temperature sensor is connected, the module responds: * , example * A + 025.51C
If temperature sensor error the module responds: * Err , example * AErr
 
Warning! The module does not respond if no sensor is connected.

[Sergio Bertana]

Each Spider module can acquire 4 sensors on the IT Bus, an address is assigned for each of the sensors. The switches can be used to assign the address range of the 4 inputs. Switches 1, 2, 3 define the addresses:

[0 0 0] - Sensor address: A, a, B, b
[1 0 0] - Sensor address: C, c, D, d
[0 1 0] - Sensor address: E, e, F, f
[1 1 0] - Sensor address: G, g, H, h
[0 0 1] - Sensor address: I, i, J, j
[1 0 1] - Sensor address: K, k, L, l
[0 1 1] - Sensor address: M, m, N, n
[1 1 1] - Sensor address: O, o, P, p

Switch 4 enables the connection to the IT Bus of clean contacts, transforming the Spider into a system for acquiring logic inputs. It is possible to have clean contacts on some spider inputs and IT Bus sensors on others.

[0] - Dry Contact: Yes
[1] - Dry Contact: No

[Sergio Bertana]

The commands for acquiring clean contacts are the same as those for acquiring temperature.

The command is: T I, example TAI
Contact open (Data IT Bus disconnected) the module replies: * , example * A000.00s
Closed contact (Data IT Bus connected with GND) the module replies: * , example * A001.00s

The closure of the contact causes the lighting of the LED located behind the IT Bus connector.

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