PiKRON ULAD 31 User manual

ULAD 31 - User Guide
PiKRON s.r.o. ( http://www.pikron.com )
April 25, 2013
Contents
1 ULAD 31 Converter Features 2
2 Setup 2
2.1 Configurationswitches ............................ 2
2.2 Device connectors and terminals . . . . . . . . . . . . . . . . . . . . . . . 2
3 Control and Communication over uLan RS-485 Line 3
3.1 Accessible Dictionary Variables . . . . . . . . . . . . . . . . . . . . . . . 3
3.1.1 Actual AD Converter Input Voltage Values . . . . . . . . . . . . . 3
3.1.2 User Scaling and Offset for A and B Channels . . . . . . . . . . . 4
3.1.3 Channel A and B Voltage Calibration Scaling and Offset . . . . . . 4
3.1.4 ADC Input Samples Filter . . . . . . . . . . . . . . . . . . . . . . 4
3.1.5 Conversion Mode of AD Converter . . . . . . . . . . . . . . . . . 4
3.1.6 ADC Input Terminals Selection . . . . . . . . . . . . . . . . . . . 5
3.1.7 ADC Sampling Period/Frequency . . . . . . . . . . . . . . . . . . 5
3.1.8 Digital Inputs Outputs . . . . . . . . . . . . . . . . . . . . . . . . 6
3.1.9 Miscellaneous Device Properties . . . . . . . . . . . . . . . . . . . 6
3.1.10 Configuration Storage to Non-volatile Memory . . . . . . . . . . . 6
3.2 Peak Selector/Solvent Recycler Setup . . . . . . . . . . . . . . . . . . . . 7
4 Producer 8
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1 ULAD 31 Converter Features
Technical Specifications of ULAD 31 :
Quantity Value Units
Supply voltage 5 to 12 VDC
Max. single unit supply current 100 mA
Max. supply current in power distribution mode 500 mA
Absolute max. analog input voltage ±15 V
Number of analog inputs (continuous acquisition) 1
Analog input multiplexer ( 2 ch. ) (optional)
Sampling frequency - basic rate 10 Hz
– optional selectable frequencies 20, 25, 40, 50, 80,
100
Basic input voltage range (gain ×1) ±10 V
Software selectable gain and range reduction ×1,×2,×4, · · · ,×64,×128
AD converter resolution for basic rate 18 to 20 bit
Width of input software filter from 1 to 64 samples
Number of digital inputs/outputs 4 / 4
Sample valve position/mark detection Yes
Communication interface RS-485
Protocol uLan
Communication baud rate 19200 Baud
2 Setup
ULAD 31 device can be connected to control/acquisition computer by USB cable or through
uLan network. To connect ULAD 31 to computer by means of uLan network another
ULAD 31, uLan to USB converter or uLan RS-485 card is required to interface uLan RS-
485 link to the PC. In the case of direct USB connection, ULAD 31 is powered by computer
over USB cable. If multiple ULAD 31 should be connected to one PC then they should be
interconected by uLan cable and only one device connected to the PC. Up to 3 more inter-
connected devices can be powered through that ULAD 31 device which is connected to the
PC if power distributed mode is selected and cables for power distribution is used (typically
white cables). If long distance or more devices are used then the power supply adapter has
to be used to provide power for other devices. Device can be even switched to USB device
disable mode to use USB connection only for power up. Independed power adapter with
USB terminal can be used to provide power supply for distant units.
2.1 Configuration switches
ULAD 31 is equipped by two switches. SW1 enables USB device interface. If disabled,
computer does not see the device but device can be powered through USB. The SW2 select
high current USB mode to receive enough power to distribute it to other interconnected
devices.
2.2 Device connectors and terminals
The next connectors can be found on the ULAD 31 device
USB connector used to connect device to a computer or to power device by power adapter
with USB terminal
2

2×uLan connectors these connectors allows to interconnect/daisy-chain multiple devices
togeter, allows use device as interface to control other uLan equipped HPLC in-
struments etc. Binder 719 series connectors are used (09 9765 2004 on ULAD 31,
09 9764 7004 on cable)
1. not connected or optional ground (GND)
2. D- connected to the cable inner wire
3. not connected or optional power supply (VCC)
4. D+ connected to the cable shielding
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1
2
4
3
Screw terminal connector analog input terminals and digital configurable input/output
signals
Terminal Signal description
1 IN1+ Analog positive signal input
2 IN1- Analog negative/reference/ground signal input
3 IN2+ Auxiliary analog input positive terminal
4 IN2- Auxiliary analog input negative terminal
5 GND Prefered use use analog input ground or shielding
6 I/O3 Digital signal 3 used for input or output
7 I/O2 Digital signal 2
8 I/O1 Digital signal 1
9 I/O0 Digital signal 0 (MARK input for default configuration)
10 GND Ground terminal for digital inputs and outputs
3 Control and Communication over uLan RS-485 Line
3.1 Accessible Dictionary Variables
3.1.1 Actual AD Converter Input Voltage Values
The ULAD converters provide single or multiple channels providing converted digital value
for input analog signal. The channels are labeled CHA, CHB etc. The CHXlabel is used
for any of the channels. As for ULAD31 there is only one continually sampled channel -
channel CHA.
Name R/W Type Function
CHA R f4 Actual value of A channel input
CHAi R s2 (/.3) Channel A as fixed value (unit 10−3)
ADCAl R s4 Raw A channel ADC value
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Actual reported channel value is obtained as result of more scaling steps applied to the raw
ADC output value:
•converter proceeds conversion according to a selected mode CHX_MODE, result is
raw value ADCXl
•value is filtered by moving averaging filter of width CHX_FILT samples
•factory preset callibration constants (CHX_CM, CHX_CA) scales value resulting
from previous steps such, that they correspond to voltage value (in Volt units) con-
nected to the ULAD 31 input (max. range ±10.000 V).
•user can select user defined scaling by constants CHX_UM, CHX_UA. The default
values of these constants are CHX_UM = 1 and CHX_UA = 0.
The steps are corresponding to the equation
CH X =CH X _UA +CH X _U M ·(CHX _CA +CH X _CM ·ADCXnorm)
where ADCXnorm is given as ratio of input voltage to the basic (jumper selected) input range
3.1.2 User Scaling and Offset for A and B Channels
Name R/W Type Function
CHA_UM R/W f4 User selectable channel A multiplier
CHA_UA R/W f4 User selectable channel A additive offset
3.1.3 Channel A and B Voltage Calibration Scaling and Offset
Name R/W Type Function
CHA_CM R/W f4 Channel A voltage calibration multiplier
CHA_CA R/W f4 Channel A voltage calibration additive
offset
3.1.4 ADC Input Samples Filter
Name R/W Type Function
CHA_FILT R/W u2
<1,64>
Channel A averaging filter length in sam-
ples
3.1.5 Conversion Mode of AD Converter
Name R/W Type Function
CHA_MODE R/W u2 ADC channel A mode
The next table describes possible MODE setting for base range ±10 V
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Gain Mode value Input voltage range
1×0±10 V
2×1±5 V
4×2±2.5 V
8×3±1.25 V
16×4±625 mV
32×5±300 mV
64×6±150 mV
128×7±75 mV
3.1.6 ADC Input Terminals Selection
Name R/W Type Function
CHA_INMUX R/W u2
<1,2>
Selection of analog input terminals
The ULAD 31 allows to select which pair of analog input terminals is connected to the
analog to digital converter. If value stored in CHA_INMUX is one (1) then IN1+/- termi-
nals are used for data acquisition. If the value is 2 then IN2+/- terminals are used. The
IN1 terminals are considered as main and this analog path is used for an factory device
calibration. The IN2 path is considered auxiliary for use where is required to check some
auxiliary state is monitored (i.e. pressure or temperature before sample analysis start) and
little worse noise parameters and calibration is not considered harmful.
3.1.7 ADC Sampling Period/Frequency
Name R/W Type Function
ADCSAMPPER R/W u2
<10,100>
Sampling period specified in milisec-
onds
The ULAD 31 is configured for 10 Hz (i.e. 100 ms) sampling rate which provides best
noise immunity to 60 Hz and 50 Hz AC mains frequency as well as other calibration and
ADC resolution parameters. The acquisition and control software reads ADC sampling fre-
quency from variable ADCSAMPPER to reflect connected device acquisition timing. The
value of the ADCSAMPPER can be modified to allow faster sampling rate if application
depends on that. Any value from 10 ms to 100 ms can be selected but voltage signal to
output value scaling is maintained only for rates given by next power of two series.
ADCSAMPPER value Sampling frequency [Hz] Sampling period [ms]
100 10 100
50 20 50
40 25 40
25 40 25
20 50 20
10 100 10
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3.1.8 Digital Inputs Outputs
Name R/W Type Function
AUXUAL R/W u2 Actual state on digital inputs and outputs
and outputs preset value
AUX_DIR R/W u2 Controls selection of input/output func-
tion for given I/Oxterminal, 1- input, 0 -
output
MARK_DADR R/W u2
<1,100>
The destination uLan address for MARK
delivery
MARK_MASK R/W u2 Mask of changes producing MARK
ULAD 31 is populated with screw terminal connector. The four digital input/output signals
(I/O1, I/O2, I/O3, I/O4) are connected to the connector contacts. Actual state of inputs and
last set value of of outputs can be read through AUXUAL dictionary variable. This variable
is used for setting of value of output signals as well. Bits corresponding to the inputs are
ignored in such case. Read and written value is equal to logical or arithmetic sum of
weights corresponding to the signals. The direction of each pin is controlled by AUX_DIR
property. If the bit/weight for given signal is set/applied then corresponding I/O terminal is
configured for input.
Signal I/O Weight
1 I/O 1
2 I/O 2
3 I/O 4
4 I/O 8
The I/O terminals configured for input can be monitored for level change and send MARK
packet when change is detected. MARK is sent to the address defined through MARK_DADR
variable. The variable MARK_MASK is used to select which I/O terminals are monitored.
The low byte of MARK_MASK variable is used to select signals to be monitored for rising
edges, high byte (basic weights multiplied by 256) is used for monitoring of falling edges.
Signal I/O Weight
Falling edge Rising edge
1 I/O 1 256
2 I/O 2 512
3 I/O 4 1024
4 I/O 8 2048
3.1.9 Miscellaneous Device Properties
Name R/W Type Function
ERRCLR E Clear device error state
3.1.10 Configuration Storage to Non-volatile Memory
Name R/W Type Function
SAVECFG E Store actual selected configuration into
EEPROM memory
Initial values of the most of writable variables are setup according to the values previously
stored in EEPROM memory at ULAD 31 power on. The values of the variables can be
written into dictionary and then stored into EEPROM by SAVECFG command invocation.
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3.2 Peak Selector/Solvent Recycler Setup
ULAD 31 programmed with the extended firmware version 1.2 can be configured to for
classification/detection of baseline and peak interval in the input signal. The input signal
is scaled through specified factory and user calibrations and moving filter of the length
CHA_FILT is applied. Obtained samples are fed to the peak selector subsystem if it is
enabled by PSEL_EN. The history window of PSEL_PWIDTH samples is analyzed and
statistical parameters are computed. If the standard deviation of the signal exceeds thresh-
old defined by PSEL_PTRESH then signal is classified as peak area and the digital out-
put(s) selected by PSEL_OUTMASK is/are activated. The output activation/deactivation
can be delayed to compensate for the length of tubing between ULAD 31 and peak selec-
tor device or solvent recycler valve. The delay on the start of the peak is configured by
PSEL_OUTDELAY variable. The output switch off is postponed by PSEL_OUTDUR.
Name R/W Type Function
PSEL_EN R/W u2
<0,1>
Value 1 enables peak selector function
PSEL_PWIDTH R/W u2 Width of analysis window in number of
samples
PSEL_PTRESH R/W f4 Threshold of standard deviation to clas-
sify signal as peak
PSEL_OUTMASK R/W u2 Bit wight mask of the digital output(s)
controlled by the classifier
PSEL_OUTDELAY R/W u2 Delay in milliseconds to switch on out-
put signal
PSEL_OUTDUR R/W u2 Duration in milliseconds to hold output
signal after classifier detects flat/baseline
signal
The function of the peak selector classifier can be monitored by next two read-only variable.
Name R/W Type Function
PSEL_ISPEAK R u2 Immediate/actual output of the
peak/baseline classifier
PSEL_VARIANCE R f4 Variance value for samples held in the
history window
The next procedure to select parameters fitting for given application follow. Check typ-
ical half-width of peaks for your separation/analysis from the record of output. Use this
value or one half of it to define time window to analyze by peak selector. The value of
PSEL_PWIDTH is computed as time window in seconds ×1000 / ADCSAMPPER which
is in milliseconds. The CHA_FILT value should be reasonably/significantly smaller than
this value or it has to be 1. Then periodically check value of PSEL_VARIANCE. The max-
imal value spotted during flat/baseline signal area should be multiplied by 2 or 3 and then
square root (standard deviation) is computed. That value is set to PSEL_PTRESH variable.
The value corresponding to the selected digital output signal is programmed to PSEL_OUTMASK.
The variables PSEL_OUTDELAY and PSEL_OUTDUR are usually set to zero for initial
run.
If optimal parameters are found they can be programmed into control computer system
initial set of the command for given analysis or they can be stored in the ULAD 31 default
parameters EEPROM store with use of SAVECFG command.
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4 Producer
Company address:
PiKRON s.r.o. Tel.: [phone]
Kankovského 1235 Mobile. : [phone]
18200 PRAHA 8
http://www.pikron.com
e-mail: [email protected]
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