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3
FACTORY CONFIGURATION
The following chart lists the programming of the unit when shipped from the
factory.
“Cal 1” -
“F or C”
- F
“tYPE”
- 2 (J)
“Cal 2” -
“AL-H”
- -50
“AL-L”
- -400
“HYS”
- 1
“Cal 3” -
“bAud”
- 3 (1200)
“Addr”
- 0
“PSEL”
- 1 (Print TC Temp.)
INITIAL SET UP
Before installing the indicator, it must be configured to the thermocouple
type and temperature scale
(F or C)
desired. Following the procedure outlined
in SET-UP and CALIBRATION, press the buttons indicated in the following
chart and observe the indicated display.
ALARM OPTION
The Apollo Thermocouple Indicator alarm option has isolated open collector
outputs for the control of temperature baths, environmental ovens, furnaces and
other industrial processes where operation within a temperature range must be
maintained. Independently programmable high and low alarm values with
programmable hysteresis
(deadband)
can be adapted to any requirement. With
the serial communication option, the alarm values may be remotely set or
interrogated by a programmable logic controller or computer. The graph depicts
how the alarms activate with hysteresis.
The Apollo display will, if selected, indicate when an alarm output is ON. If
the Alarm Display is programmed to be ON
(d ON)
, the Apollo’s display will
alternate between the T/C temperature and
“LO on”
or
“HI on”
during the time
that the respective output is ON
(the temperature is displayed for 4 seconds and
then “XX on” is displayed for 1 second)
. If the Alarm Display is programmed
to be OFF
(d OFF)
, the Apollo display will not indicate alarms.
The alarm option terminal block is located at the rear of the unit in the upper
right-hand corner. Terminals 1, 2, and 3 are used for the outputs of the alarm
option. Terminal 1 is used for the high
(HI)
alarm output. Terminal 2 is used for
the COMM.
{Note: The Alarm COMM. terminal is NOT isolated from the Analog
output VOLT- (COMM.) terminal}
Terminal 3 is the low
(LO)
alarm output.
EXAMPLE
Alarm High Value = 500° Hysteresis Value = 4° (effectively 5°)
Alarm Low Value = 470°
ALARM PROGRAMMING
Following the procedure outlined in SET-UP and CALIBRATION, press the
buttons indicated in the following chart and observe the indicated display.
In steps C, E and G, the display will first indicate what the display is and then
alternate, at a 1 second rate, between the current value and what the display is.
In steps D, F and H, when the Select button is pressed, the display will
increment first slowly and then more rapidly. The button can be released and
pressed again to increment slowly when the desired value is approached.
SERIAL COMMUNICATIONS OPTION
DESCRIPTION
The Apollo Thermocouple Indicator Serial Communication option allows
half-duplex
(two-way)
communication links to a variety of printers, controllers,
computers and terminals in order to monitor or control a temperature process.
Interrogation of thermocouple temperature, reference
(cold)
junction
temperature, and the two alarm values along with the modification of the two
alarm values provide complete remote operation. Two loops can be established;
one for sending commands to the Apollo and one for receiving data from it.
Additionally, multiple Apollos can be serially looped and assigned address
numbers. The implementation of the interface is a 20 mA loop and it is isolated
from instrument ground. This provides a high degree of noise immunity and
prevents ground loops.
An optional 20 mA to RS232C converter
(GCM232)
can be used to convert
the 20 mA loop to RS232C voltage levels.
FORMAT
Data is sent by switching current on and off in the loop and is received by
monitoring the switching action and interpreting the codes that are transmitted.
In order for data to be correctly interpreted, there must be identical formats and
baud rates. The only format available with the Apollo is 1 start bit, 7 data bits,
1 odd parity bit and 1 stop bit. The selectable baud rates are 300, 600, 1200, and
2400. These values are programmed into the Apollo.
(see programming)
.
FIG. 1: DATA FORMAT-10 BIT FRAME [300, 600, 1200, 2400 Baud]
CAL 1 INITIAL SET-UP PROGRAMMING
STEP
CAL. BUTTON
SEL. BUTTON
DISPLAY
A
X 10 secs.
CAL
0
B
X
CAL
1
C
X
D
X
E
X
F
X
TYPE CODE
0 - T, 1 - E, 2 - J
G
X
CAL
0
H
X
F or C
X
(Current Scale)
F or C
X
(Desired Scale)
tYPE
X
(Current Type)
tYPE
X
(Desired Type)
3 - K, 4 - R, 5 - S, 6 - B
888.8
8
Then TC Disp.
*
*
It is not necessary to exit to the thermocouple display if further set-up or calibration are
required, just press the “SEL” button. While in CAL
0
, select the desired CAL #.
CAL 2 INITIAL ALARM PROGRAMMING
STEP
CAL. BUTTON
SEL. BUTTON
DISPLAY
A
X 10 secs.
CAL
0
B
X
CAL
2
C
X
D
X Hold
E
X
F
X Hold
G
X
H
X Hold
I
X
J
X
K
X
CAL
0
L
X
Starts at -400 and increments to
desired value.
AL-H
X
(Alarm High) Alternating
With xxxx (Current Value)
888.8
8
Then TC Disp.
*
dxxx (Desired Alarm display
- ON or OFF).
dxxx (Current Alarm display
- ON or OFF).
AL-L
X
(Alarm Low) Alternating With
xxxx (Current Value)
Starts at -400 and increments to
desired value.
HYS
X
(Hysteresis) Alternating With
xxxx (Current Value)
Starts at 1 and increments
to desired value.
*
It is not necessary to exit to the thermocouple display if further set-up or calibration are
required, just press the “SEL” button. While in CAL
0
, select the desired CAL #.
