Red Lion DLC - Manual (Page 21)

21
SUPPORTED EXCEPTION CODES
01: Illegal Function
Issued whenever the requested function is not implemented in the controller.
02: Illegal Data Address
Issued whenever an attempt is made to access a single register or coil that
does not exist (outside the implemented space) or to access a block of registers
or coils that falls completely outside the implemented space.
03: Illegal Data Value
Issued when an attempt is made to read or write more registers or coils than
the controller can handle in one request.
07: Negative Acknowledge
Issued when a write to coil or register is attempted with an invalid string
length.
CHECKSUM ERRORS
1. Calibration checksum covers the area that contains calibration values for all
ranges. When a calibration checksum error occurs, coil 1 becomes a “1”.
2. Parameter checksum covers the area that contains the stored Holding register
settings. When this checksum error occurs, coil 2 becomes a “1”.
3. Integral and Offset/Manual Power checksum covers the area that contains the
stored Integral register settings. When this checksum error occurs, coil 3
becomes a “1”.
4. Setpoint Controller Segment Memory checksum covers the memory area that
contains the profile segments for channel A and B. When this checksum error
occurs, coil 29 becomes a "1".
5. Setpoint Controller Status Memory checksum covers the memory area that
contains the profile operating status. When this checksum error occurs, coil
30 becomes a "1" and aborts the profile putting channel in manual control at
0% power.
6. All LEDs except PWR/COMMS will flash as long as one of the errors exist.
7. The control and alarm outputs are disabled as long as one of the errors exist.
8. These errors can be cleared or activated manually by writing to the
appropriate coil. (This does not correct the reason for the error. It may be
necessary to reconfigure or calibrate.)
9. The checksums are verified at power up.
CALIBRATION USING MODBUS COMMANDS
The DLC is fully calibrated from the factory. Recalibration is recommended
every two years. Each channel is calibrated separately. All calibration settings
are stored in the non-volatile memory. The DLC may be calibrated using
MODBUS. However, the preferred method of calibrating the controller is
through the SFDLC software.
When calibrating the input, a successful millivolt calibration must be
performed first. All other input types use the millivolt points. Each input range
(non-thermocouple) also has its own internal references that are recalled when
the range is selected. Non-used types need not be calibrated.
Each of the procedures below show the calibration steps/register numbers for
both channels A & B, however, only one channel can be calibrated at a time.
Note: Allow the DLC to warm up for 30 minutes minimum and follow the
manufacturer’s warm-up recommendations for the calibration or measuring
source.
mV Calibration
Millivolt calibration requires a precision signal source with an accuracy of
0.03% (or better) that is capable of generating the range to be calibrated. It is
used for thermocouple inputs and as a basis for all other input calibration types.
1. Connect the signal source to the proper DLC terminals.
2. Enter 13 (for mV input) into register 40101 (Ch A) or 40201 (Ch B).
3. To open calibration mode, enter 48 into register 40501.
4. To start mV calibration, enter 1 (Ch A) or 101 (Ch B) into register 40501.
5. Apply the appropriate calibration voltage for a minimum of 10 seconds.
6. To store the mV calibration reading, enter the corresponding range number
into register 40501:
7. Repeat steps 5 and 6 for each range to be calibrated for that channel.
8. To save the calibration results and end calibration, enter 0 into register
40501.
Cold Junction Calibration *
Cold Junction calibration requires a thermocouple of known accuracy of
types T, E, J, K, C or N only and a calibrated external reference thermocouple
probe.
1. Connect the thermocouple probe source to the proper DLC terminals.
2. Enter the connected thermocouple type into register 40101 (Ch A) or 40201
(Ch B).
3. Enter the scale (F or C) that matches the thermometer and the controller
temperature, preferrably °C into register 40102 (Ch A) or 40202 (Ch B).
4. Enter 1 for high resolution into register 40103 (Ch A) or 40203 (Ch B).
5. Place an external reference thermometer probe at the end of the DLC probe.
The two probes should be shielded from air movement and allowed sufficient
time to equalize in temperature. (As an alternative, the DLC probe may be
placed in a calibration bath of known temperature.)
6. To open calibration mode, enter 48 into register 40501.
7. To start CJ calibration, enter 10 (Ch A) or 110 (Ch B) into register 40501.
8. Read the Process Value register 40001 (Ch A) or 40017 (Ch B).
9. Subtract the external reference reading from the Process Value register
reading. Adjust the results to tenths position, drop decimal point, and
maintain the results sign. (If the difference is -2 degrees, then adjust to -2.0
and remove decimal point yielding a value of -20.)
10. Add the value from step 9 (maintain the sign) to the value existing in register
40502.
11. If necessary, continue to adjust the register 40502 value until the Process
Value register 40001 (Ch A) or 40017 (Ch B) matches the external reference
reading.
12. To exit CJ calibration, enter 11 (Ch A) or 111 (Ch B) into register 40501.
13. To save the calibration results and close calibration mode, enter 0 into
register 40501.
RTD Calibration *
RTD calibration requires a 0.1% (or better) precision 277.0 ohm resistor.
1. Connect a precision 277.0 ohm resistor, and a short, to terminals 1 & 2 (Ch
B) or 4 & 5 (Ch A). During the complete procedure, short terminals 2 & 3
(Ch B) or 5 & 6 (Ch A).
2. Verify the input jumper is in the RTD position.
3. Enter 12 (ohms mode) into register 40101 (Ch A) or 40201 (Ch B).
4. To open calibration mode, enter 48 into register 40501.
5. To start RTD calibration, enter 20 (Ch A) or 120 (Ch B) into register 40501.
6. Leave 0 ohms (short) on terminals 1 & 2 (Ch B) or 4 & 5 (Ch A) for 10
seconds.
7. To store 0 ohm results, enter 21 (Ch A) or 121 (Ch B) into register 40501.
8. Apply 277 ohms by removing the short from terminal 1 & 2 (Ch B) or 4 & 5
(Ch A) for 10 seconds.
9. To store 277 ohm results, enter 22 (Ch A) or 122 (Ch B) into register 40501.
10. To save the calibration results and close calibration mode, enter 0 into
register 40501.
Process Voltage Calibration *
Process calibration requires a precision signal source with an accuracy of
0.03% (or better) that is capable of generating 10.00 V.
1. Connect the signal source to the proper DLC terminals.
2. Verify the input jumper is in the 10 V position.
3. Enter 14 (for voltage input) into register 40101 (Ch A) or 40201 (Ch B).
4. To open calibration mode, enter 48 into register 40501.
5. To start voltage calibration, enter 12 (Ch A) or 112 (Ch B) into register 40501.
6. Apply 0.00 V for a minimum of 10 seconds.
7. To store 0.00 V reading, enter 13 (Ch A) or 113 (Ch B) into register 40501.
8. Apply 10.00 V for a minimum of 10 seconds.
9. To store 10.00 V reading, enter 14 (Ch A) or 114 (Ch B) into register 40501.
10. To save the calibration results and close calibration mode, enter 0 into
register 40501.
* - Dependent on successful mV calibration.
104
106
105
103
102
Ch B Ch A
2
3
4
5
6
56 mV
42 mV
28 mV
14 mV
0 mV
RANGE