Troubleshooting - EasyIO - LIT-12013983 - Building Management - FW-VAV

FW-VAV Quick Start Guide

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Quick Start Guide
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Table 1. FWs troubleshooting
Problem Cause Solution
The controller does not turn on due to one of the following problems:
  • The transformer trips. Power is at the transformer primary and there is no voltage at the secondary.
  • The breaker or fuse trips. Power is at transformer primary. There is 24 V at secondary and 0 V at breaker or fuse.
The transformer shorted.
  1. Ensure that the polarity of ~24 V COM, +15 V COM, and SA BUS COM on the controller, auxiliary devices, and input and output devices is the same.
  2. Verify that the short circuit has been resolved with an ohm-meter.
  3. Reset the breaker or fuse, or replace the transformer.
    Note: When you replace the transformer, replace it with a model that uses a resettable circuit breaker. A circuit breaker makes it easier to solve wiring problems.
  4. To verify the connection, complete the following steps:
    1. Disconnect the secondary of the 24 VAC transformer.
    2. Use an ohm-meter to measure between ~24 V H and G at the controller. Ensure that no short circuit occurs.
      Note: If your installation requires that you earth ground the transformer secondary, verify that the earth ground connection is valid and not shared between multiple pieces of equipment.
The 24 VAC powered sensor is not wired with the same polarity as the controller.
The SA Bus device is not wired with the same polarity as the controller.
Analog output mode is invalid. 0 V to 10 V output is set to 100%, but output terminals are less than 10 V. Load impedance is lower than 5K ohms.
  1. Ensure that the voltage control device load impedance is higher than 5,000 ohms. For more information, refer to voltage device manufacturer specification.
  2. Disconnect the connected device and verify that the value you require is present.

Analog mode for a configurable output is invalid. For example, 0 V to 10 V output has an undesirable offset of up to 1 V. The COM terminal is not connected.
  1. Connect the COM terminal of the configurable output to the common of the connected end device.
  2. Measure the output and verify that it matches the command.
  3. Disconnect the connected device and verify the commanded value is present.
The Common Reference is incorrect.