Factory Packaged Controls Coil Products Dual Digital Module Technical Guide
Table of Contents OVERVIEW ........................................................................................................................................................ 3 Overview ......................................................................................................................................................................................3 INSTALLATION AND WIRING .................................................................................................................
Dual Digital Module Module Overview Overview The Dual Digital Module (OE370-23-DD-C) is a device that enables and modulates two digital compressors on HVAC Units controlled by the VCM-X Modular Controller (OE332-23-VCMX-MOD-C) or VCM-X Modular E-BUS Controller (OE332-23E-VCMX-MOD-C). The Dual Digital Module will control the digital compressors to satisfy the cooling, dehumidification, and heat pump requirements of the VCM-X Modular series controller.
Dual Digital Module Installation and Wiring Environmental Requirements Power Supply and Communications The Dual Digital Module needs to be installed in an environment which can maintain a temperature range between -30°F and 150°F and not exceed 90% RH levels (Non-Condensing). The Dual Digital Module is connected to the E-BUS Distribution Module with a modular HSSC cable to provide communications from the VCM-X Modular Controller.
Dual Digital Module Installation and Wiring Important Wiring Considerations 4. Be sure that all wiring connections are properly inserted and tightened into the terminal blocks. Do not allow wire strands to stick out and touch adjoining terminals. This could potentially cause a short circuit. 5. Be sure all modular wiring harness connectors are seated firmly in their respective modular connectors on the circuit board.
Dual Digital Module Installation and Wiring VCM-X Modular Controller to Dual Digital Module Wiring When using the VCM-X Modular Controller, the E-BUS Distribution Module is required ot connect to the Dual Digital Module. The Dual Digital Module connects to the E-BUS Distribution Module using a modular HSSC cable. The Dual Digital Module requires a 24 VAC power connection with an appropriate VA rating. For Stand Alone Applications, Connect To System Manager.
Dual Digital Module Installation and Wiring NOTE: Contact Factory for the correct HSSC cable length for your application. Cables are available in ¼, ½, 1, 2, 3, 4, and 5 Meter lengths and 100 and 150 Foot lengths. WARNING: Be sure all controllers and modules are powered down before connecting or disconnecting HSSC cables. OE370-23-DD-C Dual Digital Module OE365-23-EBD E-BUS Distribution Module +5V YS102308 REV 1 I2C TO COMM DIST.
Dual Digital Module E-BUS Controller to Dual Digital Module Wiring VCM-X Modular E-BUS Controller to Dual Digital Module Wiring Any E-BUS Module can be connected to the E-BUS Controller’s E-BUS port or can be daisy-chained together using HSSC cables. The Dual Digital Module directly connects to the VCM-X Modular EBUS Controller using a modular HSSC cable. The Dual Digital Module requires a 24 VAC power connection with an appropriate VA rating. See Figure 5 below for wiring.
Dual Digital Module E-BUS Controller to Dual Digital Module Wiring WARNING: Be sure all controllers and modules are powered down before connecting or disconnecting HSSC cables. For Stand Alone Applications, Connect To System Manager. For Network Applications Connect To Next Controller And/Or MiniLink PD On Local Loop. Note: All Relay Outputs Are Normally Open And Rated For 24 VAC Power Only. 1 Amp Maximum Load.
Dual Digital Module Start Up and Commissioning General In order to have a trouble free start-up, it is important to follow a few simple procedures. Before applying power for the first time, it is very important to run through a few simple checks. One of the most important checks to make before powering up the system for the first time is to make sure that the VCM-X Modular or VCM-X Modular E-BUS Controller is configured properly for your application.
Dual Digital Module Sequence of Operation NOTE: See Unit Configurations Chart on page 10 for more information about compressor staging. Off Mode Heat Pump Heating Mode (Air to Air) Heating Mode works the same as Cooling Mode except the Reversing Valve is switched and the sequence is opposite. Compressors modulate up when below the Heating Supply Air Setpoint and modulate down when above the setpoint.
Dual Digital Module Troubleshooting Using LEDs to Verify Operation The Dual Digital Module is equipped with LEDs that can be used to verify operation and perform troubleshooting. There are LEDs for communication, operation modes, and diagnostic codes. The module has seven LEDs—one used for power, one used for operation status, one used for alarms, and four used for the compressor relays. See Figure 6 for the LED locations.
Dual Digital Module Troubleshooting LED Diagnostics “PWR” LED: When the Dual Digital Module is powered up, the PWR LED (located below the address switches) should light up and stay on continuously. If it does not light up, check to be sure that the power wiring is connected to the board, the connections are tight, and the VCM-X Modular series controller is powered. If after making all these checks, the PWR LED does not light up, the module is probably defective.
Dual Digital Module Troubleshooting Temperature °F Pressure PSI Signal DC Volts See the OE275-01 Suction Pressure Transducer, Pressure, Temperature, and Voltage Chart for R410A Refrigerant testing (Table 4). The chart shows a temperature range from 20°F to 80°F. For troubleshooting purposes, the DC Voltage readings are also listed with their corresponding temperatures and pressures.
Dual Digital Module Notes Technical Guide 15
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