IIIMULTIPORT ELECTRONIC CONTROLLER

A.INTRODUCTION

The Bettis Multiport Electronic Controller (MEC) consists of a motor, Switchpak model SW20N, optional local control station and position display. It is a microcontroller based system developed to control and monitor status of the Multiport Selector Valve. It provides improved accuracy, eliminates mechanical adjustment of cams, and allows digital communication with one or more Multiport Valves over a single cable.

B.TECHNICAL DESCRIPTION

The MEC uses an optical absolute encoder to read the position of the valve into a 8 bit microcontroller. The encoder resolution is 1024 readable positions within the 360b rotation of the valve which results in the plug position being monitored to 0.35b accuracy. The microcontroller controls the motor on/off relay, and the optional digital display, with input from an external host device (computer, RTU or PLC) via a digital communication connection. The inputs from the optional local control station (switch position and pushbutton sense) are also connected to the microcontroller. The microcontroller utilizes a memory chip (EEPROM) which retains the home port setting, and ASCII text message for the valve, even during power failure.

C.ELECTRONIC CONTROLLER SPECIFICATIONS

INPUT VOLTAGE OPTIONS:

1.

120 VAC (50 - 60 Hz)

USES SOLID STATE AC RELAY AND

 

 

 

TRANSFORMER

 

2.

24 VDC

USES SOLID STATE DC RELAY AND

 

 

 

TRANSFORMER IF REQUIRED

 

 

 

BOARD INPUT VOLTAGE:

8 - 30 VDC OR 9 - 20 VAC

 

 

 

 

BOARD INPUT CURRENT:

0.5 AMP MAXIMUM

 

 

 

 

BOARD (MP-08):

CONFORMAL COATED

 

 

LIGHTING PROTECTED

 

FUSE:

1 AMP TIME DELAY

 

 

 

 

TEMPERATURE RATING:

-40bC TO +70bC

 

 

-40bC TO +85bC OPTIONALLY

 

 

 

 

SHOCK AND VIBRATION:

10 G's

 

 

 

 

HUMIDITY:

98% WITHOUT CONDENSATION

 

 

 

 

 

PROTOCOLS:

1.

ASCII BASED

CPU CHIP LABELLED "STD"

 

2.

MODBUS RTU

CPU CHIP LABELLED "MODBUS"

 

 

 

 

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