Temperature - Devair DRD 200 Instruction Manual

D. Operating check points
1. Check that green Power-on light is illuminated
2. Check that green Compressor-on light is illuminated
if dryer is on in the manual mode or it is a
scheduled on time
IMPORTANT: Refrigeration compressor must be restarted
after power interruption.
3. Check interface panel
NOTE: Interface panel will switch between Current Time/
Operating Status screen and Hours to Service/Total
Operating Hours (HRS TO SVC/TOTAL) screen. TOTAL is
cumulative hours of refrigeration compressor operation.
a. Verify that current time is correct
b. Check HRS TO SVC: this indicates time remaining
until service is required; allow time for required
maintenance items to be ordered
c. Check operating status:
MANUAL OVERRIDE - Dryer is either running
continuously (not being controlled by the
scheduled on/off times) or the refrigeration
compressor has been shut off using the
On/Off button.
SCHEDULE RUNNING - Refrigeration compressor
is being turned on and off by the monitor per-
programmed schedule ( see B.2. to set schedule)
d. Check Temperature indicator - indicator should
read in the green area
e. Check Alarm/Service light If illuminated, check
Interface panel.
1) If SERVICE DRYER appears, scheduled
maintenance time has elapsed (HRS TO SRV is 0).
Perform needed service and reset service
interval (see B.2.).
2). If ALARM appears, a dryer fault is indicated;
see Trouble-shooting Guide for possible
remedies. After fault correction push Reset
button to turn Fault alarm off.
FAULTS
LOW PRESSURE - the refrigeration compressor
control circuit has opened because of low
suction pressure. Compressor will restart
automatically when fault is corrected.
HIGH PRESSURE - the refrigeration compressor
control circuit has opened because of high
head pressure. The high pressure switch must
be reset manually once the fault is corrected.
Red reset button is located on pressure switch
inside unit.
LOW TEMPERATURE - compressed air
temperature is below the set point
NOTE: If temperature probe is open, one light on lefthand
side of Temperature indicator will be illuminated.
HIGH TEMPERATURE - compressed air tempera-
ture is above the set point.
NOTE: If temperature probe is shorted, Temperature
indicator will be completely illuminated.
DRAIN - electric drain contains a high water
level alarm that activates if drain fails to
discharge.
f. Check drain operation - push Drain (push-to-test)
button to energize electric drain. A flow of
condensate and/or air should be present at the
drain outlet.
6
E. Using the RS-232 port
The RS-232 port is used to monitor dryer operation
from a host computer. A (1 to 1) DB-9 cable is required
to connect dryer and computer. For PC connections,
data is transmitted on pin 2, received on pin 3, ground
is pin 5, pins 7 and 8 are jumpered at dryer.
Operation is at fixed baud rate of 2,400; asynchronous
format is 8 bit, no parity, 1 stop bit ("8,N,1"). No
checksum or error correction values are provided. If
required, request status string two (or more) times and
compare for agreement.
Request data by sending ASCII ? character (3FH).
Response may take up to two seconds as certain
processing functions may require completion before
serial port is acknowledged.
Dryer responds with line feed (0AH), carriage return
(0DH), and character string:
(1) (2) (3)
XXX, X, XXX, X, XXXX, XXXX, X
(1) Number of Temperature Indicator LEDs illuminated (1-20)
(2) Compressor state, C=X (1or 031H = ON, 0 or 030H= OFF)
(3) Sum of alarm weights, A=XXX (0 - 255;
e.g. high pressure and service alarms = 132 [4 + 128])
Bit Weight
2
3
5
7 128
For low and high temperature alarm, assign alarm to
number of Temperature Indicator LEDs illuminated:
3 = low, 20 = high
(4) Day of week (1 = Sunday, 7 = Saturday)
(5) Time (24 hour format, hour, minuteS)
(6) Hours to service (0-9999)
(7) Operating mode, M=X (S = schedule running,
M = manual override)
F. Using the auxiliary contacts
The monitor is equipped with an auxiliary set of dry
(volt-free) contacts (one set of normally open contacts,
one set of normally closed contacts) which can be used
to operate an auxiliary device (e.g., an air line solenoid
valve). Rating: 5 amps @ 24VDC or 240VAC
1. These contacts can be activated in one of the
following modes:
Schedule Driven Mode - the contacts will be energized
and de-energized according to the schedule inputted
by the operator of the dryer. If the refrigeration
compressor shuts down on a fault condition, the
contacts will remain energized (or de-energized)
according to the schedule. The contacts will operate
independently of the refrigeration compressor in both
the manual override and schedule running modes.
NOTE: The schedule driven mode is the factory
default setting.
For Sales & Service Call: 705-722-5747 Ext.1
(4) (5) (6) (7)
Alarm
4 High press. alarm (1 = alarm)
8 Low press. alarm (1 = alarm)
32 Drain alarm (1 = alarm)
Service (service required) alarm (1 = alarm)