RWB II PLUS MICROPROCESSOR CONTROL
OPERATION
S70-200 OM
Page 5
COMPRESSOR - Compressor displays the status of the
compressor unit. The mode of operation will be indicated as
either manual (MAN MODE) when the [RUN] key has been
pressed, automatic (AUTO MODE) when Auto Cycle has
been activated, remote (RMT MODE) when the [REMOTE]
key has been pressed, or off (OFF MODE).
V RATIO - Volume Ratio is the ratio selected by the micro-
processor to provide the highest efficiency at any given suc-
tion and discharge pressure condition. Immediately below
this, an information space has been provided to indicate
whether V ratio is in the automatic (AUTO) or the manual
(MAN) mode. The microprocessor will control this function
only in the automatic mode. To the right of the mode indica-
tor, two other messages may appear:
I - Indicates V Ratio increase.
D - Indicates V Ratio decrease.
SV POS - Slide valve position is displayed as a percentage.
This percentage reflects the mechanical position of the slide
valve and does not reflect the percentage of full load opera-
tion. Immediately below this information, space has been
provided to indicate whether SV Pos is in the automatic
(AUTO), manual (MAN), or remote (RMT) mode. The micro-
processor will control this function in the automatic mode.
To the right of the mode indicator, two other messages may
appear:
L - Indicates Slide Valve loading.
U - Indicates Slide Valve unloading.
PUMP - Pump displays the current status of the oil pump.
The display will read ON or OFF whenever the HAND-OFF-
-AUTO switch is selected to AUTO and the compressor is
running.
% FLA - Percent Full Load Amps displays the percentage of
the drive motor full load amperage rating that the motor is
currently using.
SEP - Separator displays the oil separator temperature in
degrees Fahrenheit.
HTR - Heater displays the condition of the oil separator
heater(s), indicating ON or OFF.
ALARM/CUTOUT - An Alarm or Cutout message indicates
an Alarm or Cutout setpoint has been reached, or exceeded.
Rotate the display mode to the Annunciator display for de-
tails. In the event of a cutout, rotate to the Freeze display for
further details.
FORCED UNLD - A Forced Unload message indicates that
the percentage of motor full load amps has exceeded the
maximum limit and the microprocessor is unloading the com-
pressor until the percentage FLA falls back to normal limits.
RECYCLE DELAY - A Recycle Delay message indicates
that the compressor has started and has shut down within
the time delay set point period. The Recycle Delay will pre-
vent the compressor from starting until the delay time ex-
pires and is intended to prevent damage to the compressor
motor from successive restarts. During Recycle Delay, the
microprocessor will alternatively flash “RECYCLE DELAY”
and the remaining delay time in minutes.
NOTE: Consult Motor Manufacturer for the recom-
mended duration of the Recycle Delay.
If the [RUN] key is pushed while the
unit is in Recycle Delay, the com-
pressor will start at the end of the
delay period.
C.C. - Capacity Control, located at the bottom left of the
display, indicates the current capacity control suction pres-
sure setpoint in pounds per square inch gauge (g) or inches
of mercury (hg).
ADJUSTABLE SETPOINTS DISPLAY *
ADJUSTABLE SETPOINTS: ID=[33] [10-01-87]
Cap. Control---[20.0 g ] Thu [15:33:36]
Lo Suct Cutout-[12.0 g ] Baud----[ 2400]
Lo Suct Alarm--[16.0 g ]
Hi Disch Cutout-[225 g ] Aux1[Alarm][NO]
Hi Disch Alarm--[215 g ] Aux2[Shutd][NC]
M.L.C. Stop Load--[095%] CT Factor-[078]
M.L.C. Force Unld-[100%] Recy.Delay-[30]
The Adjustable Setpoints display lists the adjustable set-
points which define the limits of the compressor package
operation. When these limits are reached, or exceeded, an
alarm or compressor shutdown will occur. The information fur-
nished by the Adjustable Setpoints display is as follows:
CAP CONTROL - The Capacity Control setpoint, reported
in pounds per square inch gauge (g) or inches of mercury
(hg), controls the loading and unloading of the compressor
when SV POS is in the automatic (AUTO) mode.
LO SUCT CUTOUT - The Low Suction Pressure Cutout, re-
ported in pounds per square inch gauge (g) or inches of
mercury (hg), will shut down the compressor if the suction
pressure drops to this limit, or lower, for 120 seconds or longer.
LO SUCT ALARM - The Low Suction Pressure Alarm, re-
ported in pounds per square inch gauge (g) or inches of
mercury (hg), will trigger a prealarm if the suction pressure
drops to this limit, or lower.
HI DISCH CUTOUT - The High Discharge Pressure Cutout,
reported in pounds per square inch gauge (g), will shut down
the compressor if the discharge pressure equals, or exceeds,
this setpoint.
HI DISCH ALARM - The High Discharge Pressure Alarm,
reported in pounds per square inch gauge (g) will trigger a
pre-alarm if the discharge pressure equals, or exceeds, this
setpoint.
M.L.C. STOP LOAD - The Motor Load Control Stop Load,
reported as a percentage of the motor full load amps (FLA),
will prevent the compressor slide valve from loading when
the setpoint is equaled, or exceeded. NOTE: Consult mo-
tor nameplate for recommended setpoint.
M.L.C. FORCE UNLD - The motor Load Control Force Un-
load, reported as a percentage of the motor full load amps
(FLA), will force the compressor to unload until the motor
full load amps (FLA) fall within 1% of the setpoint, or lower.
NOTE: Consult motor nameplate for recommended set-
point.
*Display for illustrative purposes only.
