York Millennium YCAS 310, Установка, эксплуатация и обслуживание

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FORM 201.10-NM3
107
YORK INTERNATIONAL
To program the Load Share Based On ?, key in the
number corresponding to the connected device (1=%
Slide Valve, 2=% FLA), then press the Enter key to
store the value into memory and scroll to the next dis-
play.
NOTE: It is recommended that YDAS chillers are pro-
grammed for % Slide Valve control as this will
provide better balancing between compressor
groups.
Economizer Valve On & Off Points
Economizer circuits in each refrigerant system are used
to increase chiller performance and efficiency and also
to provide compressor motor cooling at high loads. The
economizer system must be shut off at low compres-
sor loads, however, to prevent excessive liquid feed to
the compressor. This is done using a solenoid valve in
the economizer circuit refrigerant supply, based on pro-
grammable values for opening (On) and closing (Off)
the valve.
If compressor start points are controlled by % FLA (See
Load Sharing Basis value earlier in this section) the
recommended On Point is 50% and the recommended
Off Point is 40%. The Economizer Valve On Point and
Off Point values are password protected.
To program the Economizer Valve On Point, key in the
required setting and press the Enter key. This will store
the value into memory and scroll the display to the Econo-
mizer Valve Off Point message. Again key in the required
percentage value and press the Enter key. This will store
the value into memory and loop back to the beginning of
the programmable values display sequence.
3 COMPRESSOR LEAD SYSTEM SELECTION ONLY
The LEAD SYSTEM selection allows the operator to
select any one of the three compressors as the lead
when in MANUAL Lead/Lag Mode (See Section 1.12
and 3.4 (Dip Switch #7).
To program the LEAD SYSTEM NUMBER, key in the
desired number (1, 2, or 3) and press the ENTER key.
The new value will be entered into memory and the
display will advance to the next programmable limit.
E C O N O M I Z E R V A L V E
O N P O I N T 5 0 %
E C O N O M I Z E R V A L V E
O F F 4 0 %
NOTE: After selecting the lead compressor, the micro
will determine the starting sequence of the re-
maining two compressors. The sequence pos-
sibilities are shown below:
These sequences will be followed as long as anti-re-
cycle timers and safeties do not prevent it.
8.3 PROGRAMMING “DEFAULT” VALUES
Programmable values may be individually programmed
at start-up or any time thereafter. For ease of program-
ming, once the type of refrigerant is programmed in
under the Program key, a “defaults password” may be
programmed in to automatically program default val-
ues into memory. This will preset all programmable val-
ues under the Program key to values that will allow
operation of the chiller under most operating conditions.
This allows quick start-up programming for typical
chilled water applications.
To program the default values into memory, first press
the PROGRAM key followed by the ENTER key to pro-
gram refrigerant type. Press the Program key again,
key in the number “6140”, then press Enter. As the code
is being keyed, in the digits are not displayed but are
shown as “*” as shown:
When the Enter key is pressed, the following message
will appear:
Key in a “1” if default setpoints are required, or a “0” for
individually programmed values, then press Enter to
store the selection into memory.
If individual programming is selected, the display will
now return to the Status display. If default setpoints
have been selected, the display will momentarily dis-
play the message shown below before returning to the
Status display:
NOTE: It is often easier to select Default Setpoints and
then reprogram a few that require changing
rather than programming each individual value
from scratch.
P R O G R A M M O D E
* * * *
D E F A U L T S E T P O I N T S ?
1 = Y E S , 0 = N O , 1
P R O G R A M O P T I O N S S E T
T O D E F A U L T V A L U E S
LEAD
2ND 3RD
COMPRESSOR
COMPRESSOR COMPRESSOR
SELECT
1 2 3
2 3 1
3 1 2
L E A D S Y S T E M N U M B E R
= S Y S T E M # 1