FAQ - IO modules -
FAQ - IO modules
| Q |
Why do analogue modules have no isolation between channels? |
| A | Because they are all connected to the same Bussed Field Power supply. |
| < back | |
| Q |
For Non-IS (2/2) Temperature I/O modules, what does “15-bit plus sign” mean ? |
| A |
This refers to the resolution of the analog-to-digital converter within the module. The resolution is 15 bits - with a further bit reserved to indicate whether the value is positive or negative. Deduced from 2(15) = 32,768. With 15 binary bits available to relate the (absolute) value of an Analogue signal, the value can be in a range : -32768 to +32767. The Most Significant “sign” Bit is used to indicate whether the signal is positive or negative. |
| < back | |
| Q |
How do I handle frequency / counting inputs ? |
| A |
The DC Digital Input Modules feature limited pulse counting capabilities, targeted as event counters. MTL8123 Non-IS (2/2) I/O module These can count at up to 50 kbit/s. |
| < back | |
| Q |
Can I swap modules while powered? |
| A |
The MTL8000 System Railbus has been specifically designed to allow I/O Modules and BIMs to be removed and replaced without the need to remove the System Power Supply in both General Purpose and in Division 2/ Zone 2 Hazardous Area applications. |
| < back | |
| Q |
What is the input impedance of the 8201-HI-IS analogue input module? |
| A |
The specification of 15V @ 20mA available for a field transmitter already accounts for the I/O module impedance. The Input impedance is approximately 350ohms, being the sum of the safety resistor, a sense resistor, and various current limiting components. |
| Q |
8104-AO-IP Analog Output Module - Ripple & Quiescent Current |
| A |
The following is the relevant data for the 8104-AO-IP : The output ripple is 0.02% of Full scale. The quiescent current for the module, ie, the current drawn from the Bussed Field Power when all outputs are disconnected is 60mA. |
| Q |
What is the output resolution for an Analog Output (AO) module? |
| A |
12 bit resolution. This provides a range of 4,096 2(12). The electronic range of the AO module is 24 mA, resulting in a signal resolution of 1 bit = 24 / 4096 = 6 uA. |
| Q |
Can a Thermocouple I/O module be used with Grounded Thermocouples ? |
| A | Thermocouple input modules can be used with grounded thermocouples. |
| Q |
Do I need keying for general purpose modules? |
| A |
The keying arrangement on the MTL8000 Series achieves two objectives: 1) It prevents insertion of General Purpose I/O Modules in to Field Terminals connected to Hazardous Area wiring; ensuring that the User can only use appropriately protected combinations of I/O modules and Field Terminals. 2) It prevents accidental insertion of I/O Modules into a Field Terminal which has previously been keyed for an I/O Module of a different type. |
| Q |
What happens if an I/O module is placed in the wrong position? |
| A | The keying system between I/O Modules and Field Terminals prevents I/O Modules from being inserted in to the wrong position. If the keying system is somehow defeated into allowing an I/O Module of a different functional type to be used, the BIM will recognise the module type has been changed and cease any process data transactions with that module position. The BIM will not attempt any output drive to an incorrect module. |
| Q |
What happens if I add another module to a vacant slot on the carrier ? |
| A | MTL8000 2/x Modbus system: Since the module is not part of the current configuration, the BIM will not conduct transactions to this module. The BIM will only commence reading / writing to the module once the configuration is changed. In the meantime the module will show a flashing (red) fault LED to show that it is not configured. The user must employ the configurator tool to modify the node content, adding the new module with its channel attributes, and download the new file version. Once the downloaded file complies with the hardware in place, communication commences with the additional module and two-way data transactions may occur. MTL8000 2/x Profibus system: If a new module is inserted, and the host is somehow initialised into its configuration process prior to changing the configuration content, then communication with that slave will cease. This could occur by, eg, a temporary break in the LAN being restored. The configuration for that node must be modified, and the host initialised, to initiate the revised configuration process for successful operation to occur. MTL8000 1/1 Profibus system: If a new module is inserted communication with that slave will cease since an incompatibility is immediately flagged. The configuration for that node must be modified, and the host initialised, to initiate the revised configuration process for successful operation to occur. |
| Q |
How do I get status information about modules ? |
| A | The Bus Interface Module (BIM) scans all I/O modules to retrieve status information. By host program, this status information can be continuously read by the host device. |
Displaying all Legacy Products
There are no legacy products in this category