COM253 Spare Parts List and Upgrade Module Overview

COM253 is the core model of the LIQUISYS-M series transmitters, and its spare parts and upgrade modules are numerous. Based on the official spare parts list, this article organizes the order numbers, specifications, and selection key points of key modules to help engineering technicians and procurement personnel quickly locate the required components.

Spare parts are mainly divided into four categories: relay output modules, COM2x3 main modules, power supply and mounting accessories, and software upgrade packages. Correct selection can ensure system compatibility and long-term stability.

Relay Output Modules and Upgrades

Relay output modules are used to expand the digital output capability of the LIQUISYS-M basic version, supporting floating changeover contacts. Some models also integrate 4-20mA current input to meet more signal processing needs.

Relay Module Specifications and Order Numbers

Order NumberSpecificationDescription
51500320Relay output moduleUpgrade LIQUISYS-M basic version, add 2 floating changeover contacts
51511446Relay moduleUpgrade LIQUISYS-M basic version, add 2 floating changeover contacts
51500321Relay output circuit boardUpgrade LIQUISYS-M basic version, add 4 floating changeover contacts
51511447Relay module(Specifications not detailed, refer to similar)
51504304Relay output moduleUpgrade basic version, add 2 contacts and 4-20mA current input
51504305Relay output moduleUpgrade basic version, add 4 contacts and 4-20mA current input

Note: 51500321 is a 4-relay board. If cleaning function upgrade is required and this board is not installed, it must be ordered separately.

COM2x3 Main Modules and Transmitters

The COM2x3 main module is the central processing unit of the system, supporting multiple communication protocols such as HART, Profibus PA/DP. Transmitter modules are used for specific parameter measurements such as oxygen, temperature, and pressure.

Main Module Order Numbers and Specifications

Order NumberSpecificationDescription
51501225COM2x3 main moduleKIT COM2x3 Central module I1
51501223COM2x3 main moduleKIT COM2x3 Central module I1 HART
51501222COM2x3 main moduleKIT COM2x3 Central module I2
51501226COM2x3 main moduleKIT COM2x3 central module I2 HART
51501227COM2X3 main moduleKIT COM2X3 central module Profibus PA
51502500COM2X3 main moduleKit COM2X3 central module Profibus DP
71134729COM2x3 central processing modulePB DP; H/W 2.1x

Transmitters and Special Modules

  • 51501207: COM2x3 O2 transmitter
  • 51501208: COM2x3 O2 transmitter with pressure
  • 51506938: COM2x3 module MKO5 O2/temperature/pressure
  • 71134732: Relay module, including 1x Profibus DP relay module, 2x relays, 1x current input DP connection, suitable for H/W 2.10 and above

Power Supply, Mounting, and Accessories

Power supply modules and mounting accessories ensure reliable power supply and mechanical fixation of the transmitter. When selecting, pay attention to AC or DC power supply, mounting method, and material.

Power Supply and Mounting Parts List

Order NumberSpecificationDescription
51500317CXM2X3 AC power supplyKIT CXM2X3 power supply AC
51500318CXM2X3 DC power supplyKIT CxM2x3 power supply DC
51501068KIT CXM253 instrument panelKIT CXM253 housing cover
71071446Kit CxM253Front foil + 6 key lifters
51506966COM253 sensor panel socket(No detailed description)
51501073CXM253 internal mounting partsKIT CXM253 Internal housing parts
51517800Upgrade package(No detailed description)
51501072CXM253 mounting base plateKIT CXM253 bottom of housing
51501069Mounting hingesKIT hinges
51501079CXM223 terminal strip power supplyKIT CXM253 terminal strip power supply
51501074CXM253 ribbon cablesKIT CXM253 Ribbon cables
50086842LIQUISYS transmitter column mounting partFor horizontal or vertical pipe mounting, maximum diameter 60mm, material stainless steel V2A

Software Upgrade Packages and Function Expansion

Software upgrade packages can expand the functions of the LIQUISYS-M basic version, such as adding pH, conductivity, temperature, chlorine, oxygen, and other parameters, or upgrading to the S version (plus-package). Some upgrades require the instrument serial number.

Upgrade Package Order Numbers and Descriptions

  • 51500385: "Extended software" upgrade package, upgrades the basic version to the S version (adds pH, conductivity, temperature, chlorine, oxygen parameters), requires instrument serial number.
  • 51501679: COM2X3 upgrade package, upgrades the basic version (parameter DO) to the S version, requires instrument serial number.
  • 51500963: "Cleaning function" upgrade package, adds Chemoclean cleaning function, requires instrument serial number. If the 4-relay board is not installed, 51500321 must be ordered separately.

When purchasing upgrade packages, be sure to confirm the current hardware version and serial number to ensure compatibility.

Selection Recommendations and Precautions

  1. Confirm the basic version of the existing system and installed modules to avoid duplicate ordering.
  2. Select the main module according to communication requirements: HART, Profibus PA, or DP.
  3. Relay modules need to distinguish the number of contacts and whether they have current input.
  4. Power supply modules need to match the on-site power supply type (AC/DC).
  5. Software upgrade packages require the instrument serial number, and hardware compatibility should be checked.

Correct selection can maximize system performance and reduce downtime. If in doubt, it is recommended to consult official technical support.