York Millennium YCAS 310, Установка, эксплуатация и обслуживание

Страница: 75 / 124

FORM 201.10-NM3
75
YORK INTERNATIONAL
3.3 AMBIENT TEMP KEY
When the Ambient Temperature key is pressed ambi-
ent air temperature as measured surrounding the chiller
is displayed.
Display Limits: Minimum – 4.6°F (–20.3°C)
Maximum 137.9°F (58.8°C)
3.4 SYSTEM PRESS / TEMP KEYS
Pressing one of the System Pressures / Temperatures
keys a number of times scrolls through six displays giv-
ing differential oil pressure (OIL), suction pressure (SP)
and discharge pressure (DP), suction (SUC) and dis-
charge (DSCH) temperature, oil temperature saturated
discharge and suction temperature, compressor slide
valve position and compressor suction superheat.
Examples of these displays are as follows where # is
the appropriate system number:
(Suction temperature is not given on 50 Hz models.)
(Superheat is not given on 50 Hz models.)
Temperatures and pressures are either measured di-
rectly by transducers and temperature sensors, or com-
puted from these measurements as follows:
S Y S # O I L = 1 5 P S I D
S P = 5 5 D P = 2 4 8 P S I G
S Y S # S U C = 3 6 . 2 ° F
D S C H = 1 2 1 . 2 ° F
O I L T E M P # = 7 7 . 9 ° F
S A T D S C H # = 1 3 0 . 0 ° F
S A T S U C T # = 2 4 . 3 ° F
S Y S # S L I D E V A L V E
P O S I T I O N = 1 0 0 %
S Y S # S U P E R H E A T
= 1 2 . 2 ° F
A M B I E N T A I R
= 7 1 . 9 ° F
Differential oil pressure is the pressure difference be-
tween oil leaving the discharge separator and oil pres-
sure reaching the compressor. It is computed by sub-
tracting oil pressure measured after the oil line filter
from discharge pressure (oil in the oil separator is at
discharge pressure). Typically for a clean oil filter the
drop will be 2 – 10 PSID (14 – 69 kPa) but may reach
up to 40 PSID (276 kPa).
Saturated discharge and suction temperatures are com-
puted by converting measured pressure to tempera-
ture.
Slide Valve Position is computed from average % FLA
motor current, discharge pressures and the number of
load pulses sent to the compressor.
NOTE: Slide valve position is approximate and should
be used for reference only. Under many condi-
tions, it will read well below 100%, possibly as
low as 60%, when a compressor is fully loaded.
Superheat is computed by subtracting saturated suc-
tion temperature from suction temperature.
Display Limits are as follows for the System Pressures
and Temperature displays are as follows:
NOTE: Minimum and maximum values may change
as software (EPROM) revisions are made.
NOTE: *Below 9.0°F the Suction Temp. display will dis-
appear. This will in turn cause the Superheat
display to disappear.
MIN. LIMIT MAX. LIMIT
Oil Pressure 208 PSID 0 PSID
Suction Pressure 0 PSIG 199 PSIG
Discharge Pressure 0 PSIG 399 PSIG
Suction Temp. *9.0°F 84.2°F
Discharge Temp. 40.3°F 302.6°F
Oil Temp. 40.3°F 240.0°F
Sat. Discharge Temp. –41.0°F 140.5°F
Sat. Suction Temp. –41.0°F 101.3°F
Slide Valve Position 0% 100%
Suction Superheat *–81.5°F 60.9°F