The Model 600 Lead/Lag Controller is the ultimate low-cost HVAC automation solution for critical facilities, offering unmatched performance, reliability, and energy efficiency. With its rugged design, intuitive display/keypad, seamless setup process, and Quest’s patented economizer control algorithm, the Model 600 exceeds comparable devices in the market.
Whether you’re managing Telecom, Broadband, Data Centers, or Power Utility facilities, this controller is designed to meet your needs by providing comprehensive monitoring and control for multiple HVAC units. It supports lead/lag or lead/standby configurations for two HVAC units and delivers flexibility to handle wall packs, rooftops, split systems, single-stage, dual-stage systems, and heat pumps with exceptional dependability.
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Optimized Energy Efficiency
Quest’s patented economizer control algorithm ensures your HVAC units maximize the use of outside air to maintain optimal temperature while minimizing energy consumption. When networked with Quest's TELSEC® ESB2 system, a single outside air sensor can be shared across all Model 600 controllers for streamlined operation.
Built for Critical Facilities
The Model 600 provides essential redundancy and reliability for critical facilities where downtime is not an option. Its advanced features reduce costs while giving you confidence that your facility operates at peak performance.
Why Choose the Model 600?
The Model 600 is more than just an HVAC controller—it’s a smart solution that provides:
Energy Savings: Reduce energy consumption while maintaining optimal facility conditions.
Reliability: Ensure redundancy and dependable operation in critical environments.
Flexibility: Adapt to various HVAC system configurations with ease.
Convenience: Enjoy remote communication capabilities via Ethernet or Bluetooth for effortless monitoring and adjustments.
Key Features
- Versatile HVAC Compatibility: Configurable to control single-stage, two-stage, or heat pump systems.
- Economizer Control: Works with existing HVAC economizer modules using Quest’s patented algorithm for optimal energy savings.
- Dual Power Sources: Powered by two HVAC 24VAC transformers with additional support for 24VDC or 48VDC power sources.
- Standalone Operation: Operates independently if communications
are lost. - Network Integration: Compatible with TELSEC® ESB2 or any Modbus poller for seamless networking.
- User-Friendly Interface: Includes an LCD display showing operating mode, alarms, and temperature readings, plus a five-button keypad for easy navigation and configuration. Additionally, default settings and configurations can be securely adjusted through password-protected screens.
- Bluetooth Connectivity: Communicates with Quest’s mobile app for convenient monitoring and control.
- Ethernet Connectivity: Built-in webserver and Modbus TCP support allow remote access to settings and configuration via Modbus or a web interface.
- Advanced Sensor Support: Supports two zone temperature sensors, an outside air sensor, and an optional humidity sensor. The controller calculates controlling temperature using either the average or high value of zone sensors.
- Optimal Economizer Control: Standalone economizer functionality enabled by the outside air sensor ensures efficient operation.
Connect several Model 600 HVAC controllers to the TELSEC ESB2 system.
Setpoints
The Model 600 setpoints are field changeable via password.
| Standalone mode - cool 1 on | 76 |
| Standalone mode - cool 2 on | 78 |
| Standalone mode - All cooling off | 74 |
| Standalone mode - heat 1 on | 55 |
| Standalone mode - heat 2 on | 53 |
| Standalone mode - All heating off | 60 |
| Standalone mode - fan operation | Auto |
| Network mode - cool 1 on | 78 |
| Network mode - cool 2 on | 80 |
| Network mode - All cooling off | 74 |
| Network mode - heat 1 on | 50 |
| Network mode - heat 2 on | 48 |
| Network mode - All heating off | 53 |
| Network mode - fan operation | On |
Applications
- Utilities/Telecommunication/Cable & Broadband – Remote Cabinets & Shelters
- Data/Switching/Computer Centers/COs/Headends & Hubs
Specifications
Support Documents
Quest's HVAC Controllers
Model 100 & 101 Lead/Lag Controller
Model 200 & 201 Lead/Lag Controller
Model 400 HVAC Controller
