Emerson VISSION 20/20 service manual Timers

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Timers

True Anti-Recycle Timer = Once the compressor turns off, this timer will keep the compressor off for the setting of the True Anti-Recycle Timer. This timer is used to prevent short cycling of the compressor.

Accumulative Anti-Recycle Timer = This timer also forces a specified time between compressor starts. When the compressor starts, the timer resets and starts timing and accumulates running time. Once the compressor shuts down, it will not be allowed to restart for the remainder of time left on the Accumulative Anti-Recycle Timer. Unlike the True Anti-Recycle Timer, if the compressor has run for a time period that exceeds the set- point of the Accumulative Anti-Recycle Timer, then when the compressor shuts down, it will be allowed to restart immediately.

As an example:

Accumulative Anti-Recycle Timer setting = 20 minutes.

Assume the compressor starts and runs for 15 minutes then shuts down.

The next start can occur in (20 minutes - 15 minutes of runtime = 5 minutes)

The compressor restart options (Hot Starts or Anti-Recycle Timers) are selected from the “Configuration” menu. One additional Anti-Recycle Timer is selected from the Configuration menu, which is the “Modified Anti- Recycle” timer. Modified Anti-Recycle Timer = This timer has no direct set-point. It is defined as a combination of the True Anti-Recycle Timer and the Accumulative Anti-Recycle Timer. Normally when the “Modified Anti- Recycle Timer” function is selected from the Configuration menu, the timer functions as a True Anti-Recycle timer and uses the set-point of the True Anti-Recycle timer. However if the operator presses the stop button, or if a failure occurs, then the Modified Anti-Recycle Timer function switches to activate the “Accumulative Anti-Recycle Timer”. As the definition of the Accumulative Anti-Recycle Timer states, now the compressor will be allowed to restart when the present accumulated runtime and the present accumulated off time meets or exceeds the setting of the “Accumulative Anti-Recycle Timer”.

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Contents Control Panel Page Important Note Page Touch Screen LCD Display Optional Analog Input Jumper Tables Standard Vilter Warranty Page Operational Flow Charts Page Voltage Source Proper Wire SizingVoltage Source Grounding Mixing Voltages Wiring Methods DON’T Touch Screen Description Type Liquid Injection #2 Output Not Defined Page Analog Inputs Page Compressor VFD 20 mA Condenser VFD Slide Valve Position Main Screen Touch Screen LCD DisplayMenu Button LOG on Button IndicatorsMenu Screen Page Compressor Control Time Proportioning Control Auto-Cycle Setpoints Other Setpoints That Might be Required for Motor PID Control Pump-down Pull-down Misc. Control Page Page Alarms and Trips Screen Page Alarms and Trips Page Timers Page Timers Service Options Instrument Calibration Slide Calibration Remove Cover Press Down On Photochopper Command Shaft Rotation Capacity Volume INC DEC CCW Slide Valve Operation Problem Reason Solution Slide Valve Trouble Shooting GuideProblem Replace the actuator. See above Trend Chart Event List Screen Input / Output States Configuration Screens Page Page Maintenance Screen Log In Screen Screen to Add Users User Level Suction Pressure SP#2 Fail Percent Volume FailLow Control Temperature Fail Suction Pressure SP#1 FailLow Oil Injection Temp Fail Auxiliary Safety#1 Input FailLow Start Oil Pressure Fail Low Oil Pressure FailVission 20/20 Troubleshooting Guide Digital & Analog Boards DipswitchesDipswitch Position Digital Output #2 Digital Input Digital Input/Output #1 Digital Input/Output #2 POSITION-1 JP-16 JP-19 JP-22 JP-27 JP-28 JP-29 JP-30 JP-31 POSITION-2 Jumper Position Analog Output Optional Analog Input Jumper Tables Channel #6 Signal Page EmersonClimate.com