UC-1203, a module for connecting the MP-Bus actuators

TCL2 modules 18.03.2020 16:28 18.03.2020 16:28

The UC-1203 module is used for connecting Belimo regulating actuators via the MP-Bus (a Belimo company product). The module makes it possible to connect up to 8 regulating actuators (globe valves actuators, and regulating ball valves actuators) on the MP-Bus. Some actuators can also be connected to an external sensor (active/passive), which is also processed by the UC-1203 module. It takes approximately 700ms to operate one of the connected actuators, which means that it takes about 5.5s to operate all eight actuators. When operating the actuators, it is necessary to take into account this delay in the application program.

The module is powered by an external 24VDC power supply, which is not galvanically isolated from the internal circuitry, but it is galvanically isolated from the MP-Bus interface.

The module is fitted with screw terminals for a maximum wire cross-section of 2.5 mm2 per terminal.The terminal block serves for connecting the TCL2 communication line, for powering the module and for connecting the MP-Bus.

The module is in a plastic 1M box (17.5 mm wide); the dimensions are listed in Chapter 13.2.4.

 

Tab. 1 Basic parameters of the UC-1204 module

System bus

TCL2

Supply voltage

20.4 ÷ 28.8 VDC

Maximum power consumption

2.5 W
 

 

Galvanic isolation from the MP-Bus

yes

Operating temperature

-20 ÷ +55 °C

Working position

free

Installation

on a DIN rail

Connection/wires cross-section

screw terminals / max. 2.5 mm2

MP-Bus level high

min. 11 V typically 15 V max. 18 V

MP-Bus level low

max. 2.5 V

MP-Bus current to short circuit

max. 10 mA

Communication speed / byte structure

1200 baud / 1 start, 8 data, 1 stop, no parity

Data transfer

bidirectional, half duplex

The number of connected slaves

8

 

 

 

Brief information on the MP-Bus

The MP-Bus is a master-slave bus designed by Belimo. Up to 8 slave actuators can be controlled by one master module (UC-1203) - flap actuators, valve actuators (MP/MFT). One actuator can be connected to one sensor - e.g. with 0 to 10 V output, contact, Pt1000, Ni1000 or NTC temperature sensor.

The MP-Bus consists of three wires - 24 VAC or DC power supply, common GND signal and communication wire called MP. All three wires are in one cable. There is no need for any special cable or bus termination.

The bus topology is arbitrary. Permissible topologies include star, ring, tree and mixed configurations.

Maximum cable length is determined by the wire diameter, power consumption of the actuators (depending on the type) and by the power supply (AC or DC); for more calculation details see the Belimo company documents.

E.g. for 4 actuators with a total power consumption of 13.5 W distributed in a single cable, 24 VDC power supply, with 1.5 mm2 cross-section, the maximum cable length is 110 m; with the cross-section 2.5 mm2 the maximum length is 190 m.

 


Fig. 1 A basic example of Belimo actuators connection to the UC-1203 module

 

Notes:

  1. Connecting Belimo actuators to the UC-1203 module is done using the 24 V ~ / GD / MP terminals. The UC-1203 module does not supply power for the controlled actuators; they must be powered from a 24 VAC/DC external source.

  2. In order to select the capability of power supplies, you should calculate the maximum bus length and the cross-section of wires for the MP-Bus, see the Belimo company documentation; for a brief description see higher up in this text.