York YK-EP, Operation And Maintenance Manual

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If a power failure occurs while the trending is running, the trending is stopped. Upon restoration of
power, the last screen of data that was collected will be displayed on the TREND Screen. The START
key must be pressed to initiate a new TREND Screen.
Display only
This screen allows the user to view the graphical trending of the selected parameters and is also a
gateway to the graph setup screens.
Note: A red screen with the words “TREND MAX MUST BE > TREND MIN” will appear if the Y-
Axis minimum has been programmed to a value that is greater than the Y-Axis maximum for
any parameter. If this appears, proceed to the TREND SETUP Screen to change the values.
Table 185: Programmable
Button Access level Description
Start Operator
Pressing this key clears the graph, starts a new graph, sets the time
of day to the present clock time and begins the trending. This key
is only available if trending is stopped. If the selected Chart Type is
triggered and Trigger Action is set to Start, data collection will not
begin until the triggers have been satisfied and any selected trigger
delay has elapsed. Otherwise, data collection will begin immediately.
Stop Operator
Pressing this key stops the trending. The trend data is frozen on the
display until another graph is started with the START key. The STOP
key is only available if trending is running.
Print View
Allows the data on the TREND Screen to be printed in tabular
format. If set to existing, a snapshot of the data presently on the
screen is sent to the printer. If set to new, all data collected after
pressing this key will be sent to the printer as it is collected. If set
to disabled, no data is sent to the printer. Refer to Printing of this
manual for printout example.
Data Select View
Allows the user to display all trended data points simultaneously or
select a single trended data point for display, hiding the other data
points. Selections are All Data or Data Point X (1-6).
Y-Axis View
This key toggles the Y-Axis labels of the graph. Each key press
changes the label to another of the selected parameters.
X-Axis View
This key toggles the X-Axis labels of the graph. Each key press
alternates the scaling between time of day and elapsed time. The
Time of Day scaling is in 24-hour format. The Elapsed Time scaling
is the time elapsed since the START key was pressed, starting the
trending.
Table 186: Navigation
Button Access level Description
Home View Returns user to HOME Screen.
History View Returns user to HISTORY Screen.
Trend Setup –
Only displayed if the trending is stopped. Causes a jump to a
subscreen for configuring the trending display
177 YK-EP Style B Centrifugal Chiller