Emerson 20/20 Restart On Power Failure, Compressor Sequencing, Language, Model & Refrigerant

Section 19 • Configuration

due to repeated motor starts. The operator has 3 choices of protection. Hot starts allows only a certain number of starts per hour before setting an hour to the anti-recy- cle timer. The number of starts is set in the timer page. Accumulative immediately adds time to the anti-recycle timer once the compressor is started and the time can be set in the timers screen. True anti-recycle adds to the anti-recycle timer once the compressor is shutdown. The motor of the compressor can not be restarted as long as there is anti-recycle time left and the operator can view this time on the top left corner of the main screen.

Restart On Power Failure

This feature of the Vission 20/20 offers the ability to de- fine how the Vission 20/20 will handle a power failure. This can also be useful to allow system controller to re- gain control of the Vission panel without the need for operator intervention.

Always:

•When selected, initiates a start after the panel pow- ers back up after a power failure, but only if the com- pressor was running before the power failure and starts the compressor in Auto mode.

Never:

•When selected, prevents any automatic action once the panel powers back up after a power failure.

Timed:

•When selected, initiates a start after the panel pow- ers back up after a power failure and the operator set timer runs out. When there are multiple compressor in a larger system, it is recommended that the opera- tor gives each compressor a different start times. A restart will only occur if the compressor was running before the power failure and starts the compressor in Auto mode.

Remote Lock Off:

•When selected, turns the remote lock out off when the panel powers up. Select this option if the opera- tor wishes a system controller to regain control of the Vission 20/20 without human interference.

Boot in Remote (Direct I/O)

•When selected, places the panel into remote mode when the panel powers up. Select this option when under direct I/O control and the system controller is to gain control of the Vission 20/20 without human interference.

Compressor Sequencing

The compressor sequencing is a feature of the Vission 20/20 that allows the operator to setup as many as five compressor to automatically start, stop and maintain system loads. The compressor that is designated as the master will monitor systems parameter and make deci- sions on how many compressor are required to meet the load as efficiently as possible.

Compressor Sequencing:

•Enables the compressor sequencing algorithms and allows access to the compressor sequencing screen.

Master:

•Identifies the panel as the master while in sequencing control.

Slave:

•Identifies the panel as a slave while in sequencing control.

Compressor Name:

•Unique identifier that is broadcasted to all other Vission 20/20 units in the sequencing network.

Language

Allows the operator to select the language in which all screens will be displayed in.

Model & Refrigerant

The values in this section provides the Vission 20/20 algorithm critical information on how to efficiently and safely control the compressor, see Figure 19-2. Configuration Screen - Page 2.

Compressor:

•Drop-down box to select the compressor type. This selection is critical for proper volume slide control.

Model:

•Drop-down box to select the compressor size. This selection is critical for proper volume slide control.

Refrigerant:

•Drop-down box to select the type of refrigerant. This selection is critical for proper volume slide control.

Other (K-Factor):

• Optional setting to adjust volume slide control.

Vission 20/20 • Operation and Service Manual •Vilter/Emerson • 35391SC 1.8.5153 19 – 3