ABB 81EU01-E/R3210 Input Module for Analog Signals

ABB 81EU01-E/R3210 Input Module for Analog Signals

DESCRIPTION

The module incorporates a total of 5 function units. Each function unit may be used for any type of input mode. Any combination is possible. The allocation as well as the settings of all the parameters can be programmed easily using the configuration list. The programmed values are stored in an EEPROM to ensure that they are not lost in the event of a power failure. They can be changed any time. Every analog signal can be assigned up to 4 limit values. In an input module, up to 5 independent correction or filter calcuations can be carried out. Programming is done by structuring function blocks. The conditions relevant to this application are to be taken into consideration.

Application

The input module is used as a substitute for the following input modules with transmitters:

81EA01-E/R1010 without correcting function 

- 2-wire transducer, 4 ... 20 mA, with supply from the module 

- 4-wire transducer, 0/4 ... 20 mA, with supply from the module 

- 4-wire transducer, 0/4 ... 20 mA, with external power supply

81EA01-E/R1111 with correcting function and without output of the uncorrected value (raw value) 

- 2-wire transducer, 4 ... 20 mA, with supply from the module 

- 4-wire transducer, 0/4 ... 20 mA, with supply from the module 

- 4-wire transducer, 0/4 ... 20 mA, with external power supply

81EA01-E/R1112 with correcting function and output of the uncorrected value (raw value) 

- 2-wire transducer, 4 ... 20 mA, with supply from the module 

- 4-wire transducer, 0/4 ... 20 mA, with supply from the module 

- 4-wire transducer, 0/4 ... 20 mA, with external power supply

Features

The module can be plugged into any PROCONTROL station with an external power supply unit. It is equipped with a standard interface for the PROCONTROL station bus. The module sends the converted input signals in the form of telegrams over the station bus to the PROCONTROL bus system. The telegrams are checked before they are sent and marked with test flags. This ensures that the receiving module can check them for error-free transmission.

The telegrams received over the station bus, e.g. for correction calculations, are checked by the module for error-free transmission based on their test flags. Provision is made to eliminate interference among the function units of the module and the station bus. A short-circuit-proof and monitored transmitter power supply is available for each function unit, suitable for the various applications.

A response of the internal monitoring circuits or of the input signal monitoring function is indicated in the form of a disturbance annunciation ST (general disturbance) on the front panel of the module.

Application with analog transmitters

Types of transmitters

The function units of the module can be used for 

- 2-wire transducers, 4 ... 20 mA, with supply from the input module 

- 4-wire transducers, 0 ... 20 mA and 4 ... 20 mA, with supply from the input module 

- 4-wire transducer, 0 ... 20 mA and 4 ... 20 mA, with external power supply of the transducer

Transducer power supply

The transducer power supply from the input module is shortcircuit-proof, coming from the respective supply output USn, and is monitored inside the input module. In the case of an external power supply for a transducer, the supply contact of the function unit concerned remains free. The maximum potential difference between the different reference potentials has to be taken into consideration in the case of external power supply. It is not admissible to connect several USn supply outputs in parallel.

Analog signal input circuit and monitoring

At a high-accuracy measuring resistor, the input current signal is converted into a measuring voltage, connected to the input instrument amplifier via a multiplexer and, after that, converted into a digital 12-bit analog signal by an A/D converter. The input instrument amplifier and the A/D converter are monitored with the help of reference voltages. The analog signals are monitored for plausibility inside the module. The monitoring function responds as soon as an upper limit (OG) or a lower limit (UG) is violated. These limits can be modified in the configuration list. Their default setting is 118.75 % for the upper limit and -6.25 % for the lower limit.

Plausibility monitoring can be suppressed separately for each function unit. For this purpose, the maximum values for the upper and lower limits need to be entered into the configuration list. The digital 12-bit signal is completed by the correct sign and is sent by the input module as a telegram to the station bus. As soon as the analog signal monitoring responds, the analog value telegram will be sent with the disturbance bit set.