Questions? Call us! (918) 663-9321

Specific Systems Quadraplexor Control Panel HMITake control of your HVAC with our multiplexors

Many of our customers require N+1 redundancy for the HVAC on their buildings. Our multiplexor control panel is an option provided for applications that require multiple HVAC systems. This allows additional redundancy, often desired for unattended sites, and provides several standard services including:

  • Auto-sequencing between systems, based on 24-hr timer
  • Manual selection of any HVAC system in the circuit
  • Automatic dual-unit operation – High or low temperature condition
  • High Temperature Alarm – Form C dry contacts

The multiplexor is a microprocessor based PLC control panel for controlling multiple Specific Systems® units. If a failure of the main unit occurs (determined through use of multiple sensors inside each unit), the multiplexor automatically energizes another system to keep the area pressurized and can provide an audible or visible alarm to notify personnel of the failure. 

All multiplexors include the ability to manually override and lockout main unit. Override of the main unit can also be caused by a power-failure of the main unit or a high/low temperature alarm. Multiplexors are enclosed in hinged 6" deep NEMA 4 enclosures from 16"×14" to 30"×30", based on required interior components.

These panels are shipped ready for remote mounting as well as remote monitoring.

Custom Control Packages

LonWorks/BACnet Systems Integration


  • Realtime temperature monitoring
  • Realtime filter monitoring
  • Economizer controls
  • Remote start/stop of HVAC equipment
  • Remote HVAC alarm monitoring


Specific Systems® is proud to offer LonWorks/BACnet controls for our InPac® units. Since many units are placed in remote locations, immediate notification and remote diagnostics of alarms can reduce downtime and minimize expensive on-site service trips.

With LonWorks/BACnet controls, customers can work with our engineers to create operation sequences that meet their project specifications.

The products are microprocessor-based programmable controllers designed to control various I/O. Expansion modules are available, giving this controller a total of up to 40 universal inputs and 36 universal outputs. These controllers use the LonTalk® communication protocol and are LonMark certified as a Static Programmable Device, or BACnet, guaranteeing compatibility and interoperability with other manufacturers’ LonMark certified controllers.

Several options are available, each with universal inputs and outputs that are ideal for controlling Specific Systems®’ HVAC equipment. One option includes a full-color backlit-display and a jog dial for turn and select navigation to access a wide range of internal controller functions: view, set, and override values, view and modify schedules, tune PID loops with system response graphing, and view connection and communication alarms. Other models include the convenience of supervised Hand-Off-Auto (HOA) switches and potentiometers for supervised manual override of an output.

Supported Platforms

The EC-NetAX multi-protocol integration solution is web-enabled and powered by the NiagaraAX Framework, establishing a fully Internet-enabled, distributed architecture for real-time access, automation and control of devices. The EC-NetAX open framework solution creates a common development and management environment for integration of LonWorks®, BACnet® and other protocols. Regardless of manufacturer and protocol, the EC-NetAX system provides a unified modeling of diverse systems and data, providing one common platform for development, management and enterprise applications.

The LNS® client-server platform allows multiple users, running different LNS-compatible applications, to access a common source for directory, installation, management, monitoring and control services for the network system being managed. Distech Controls’ Lonwatcher is an example of a LNS-based network management tool that can use Plug-Ins to configure and monitor controllers and devices in the control system.

Optional Add-ons

  • Occupancy override
  • Indoor/outdoor remote temperature sensor

Available Options

Available Options

As part of our control packages, we offer these and other options.

  • Touchscreen HMIs
  • NEMA 4X enclosures
  • Remote temperature sensors

Need more information?

Let us help you get the correct HVAC system for application.

Request Info

Go to top