Trane CVGF manual Standard Protections, Short-CyclingProtection

Models: CVGF

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Short-Cycling Protection

Controls

Standard Protections

Short-Cycling Protection

This function mimics heat dissipation from a motor start using two setpoints:

Restart Inhibit Free Starts and Restart Inhibit Start-to-Start Timer. This allows the CVGF to inhibit too many starts in a defi ned amount of time while still allowing for fast restarts. The default for CVGF is 3 Free Starts and a 20 minute Start-to-Start Timer. The control panel generates a warning when the chiller is inhibited from starting by this protection.

Restart Inhibit Free Starts

This setting will allow a maximum number of rapid restarts equal to its valve. If the number of free starts is set to 1, this will allow only one start within the time period set by the Start-to-Start Time setting. The next Start will be allowed only after the Start-to-Start timer has expired. If the number of free starts is programmed to 3, the control will allow three starts in rapid succession, but thereafter, it would hold off on a compressor start until the Start-to-Start timer expired.

Restart Inhibit Start-to-Start Time setting

This setting defi nes the shortest chiller cycle period possible after the free starts have been used. If the number of free Starts is programmed to 1, and the Start-to-Start Time setting is programmed to 10 minutes. the compressor will be allowed one start every 10 minutes The Start-to-Start time is the time from when the motor was directed to energize to when the next prestart is issued.

CTV-PRC001-E4

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Trane CVGF manual Standard Protections, Short-CyclingProtection