background image

Page 6 

Operation of the instrument 

4.1  Connecting up the microDAQ. 

The microDAQ has one connector and cable which supplies the unit with power and also provides 
CAN  and  Ethernet  comms.  Ensure  all  the  connections  are  made  before  powering  up  the 
microDAQ. 

The microDAQ should not be hot plugged with the power connector. Doing so can 

cause permanent damage to the unit. Always switch the power at the power supply source.

  

 
Upon  power  up,  the  blue  LED  will  light  constantly  while  the  microDAQ  boots  up.  This  boot-up 
period will vary depending on the type of scanner and the number of channels. The boot up time is 
also  influenced  by  the  Ethernet  initialisation  process.  This  process  requires  a  valid  network 
connection to perform auto negotiation and link check  status.  If there isn’t a valid connection the 
process waits until either a network is found or the timeout occurs. This timeout is configurable via 
setup and ranges from 0 to 30 secs per check (2 checks). 
 
When the microDAQ has finished booting, the blue LED will flash at a constant rate to show that 
the system is running (unless auto hardware trigger enable has been set – see later).  

 

4.3  Re-zeroing the microDAQ. 

Before  any  measurements  are  made,  the  microDAQ  should  be  re-zeroed.  The  microDAQ  may 
need further re-zeroing if the unit or scanner should be subject to significant thermal variations. 

 

The microDAQ is re-zeroed by sending the appropriate command over the CAN or Ethernet link via 
the Chell software. The system will then average a number of zero readings and perform a re-zero. 
Naturally, there should be no pressure applied to the ports of the scanner when a re-zero is being 
performed. 
 
When a re-zero is being performed, the red LED will light momentarily. 

 

Summary of Contents for microDAQ-Mk2

Page 1: ...Road North Walsham Norfolk NR28 0AJ ENGLAND Tel 01692 500555 Fax 01692 500088 microDAQ Mk2 Pressure Scanner Acquisition System INSTALLATION AND OPERATING MANUAL e mail info chell co uk Visit the Chell...

Page 2: ...ied in this manual may impair the user s protection Chell Document No 900193 Issue 1 3 ECO 2230 Date 9th May 2016 Chell s policy of continuously updating and improving products means that this manual...

Page 3: ...erver 8 5 1 Introduction 8 5 2 Common Controls Sidebar 9 5 3 The Setup Page 9 5 3 1 Introduction 9 5 3 2 Data Streaming 9 5 3 3 TCP Parameters 10 5 3 4 UDP Parameters 10 5 3 5 CAN Parameters 11 5 4 Li...

Page 4: ...date both conventional HD series scanners and Digital Thermal Compensation DTC scanners with 16 32 and 64 channels The microDAQ is supplied with all the software required to configure it and read the...

Page 5: ...ons USB2 0 micro 57600 baud no parity 8 data bits and 1 stop bit 2 4 Ethernet Specifications TCP IP 10Mb s 100Mb s via Auto Negotiation TCP UDP protocols supported 2 5 Operating conditions Operating t...

Page 6: ...ge to the unit Always switch the power at the power supply source 3 3 Scanner Connector Internal micro miniature D type female Pin number Signal 1 Address line A0 2 Address line A1 3 Address line A2 4...

Page 7: ...atus If there isn t a valid connection the process waits until either a network is found or the timeout occurs This timeout is configurable via setup and ranges from 0 to 30 secs per check 2 checks Wh...

Page 8: ...d set and so on When the hardware trigger is activated the microDAQ will wait for the first pulse The time that this first pulse is generated can be measured by the user and therefore the time of the...

Page 9: ...s the tools for performing a new calibration namely calculating and downloading new coefficients and the means to managing calibration data Data from the calibration procedure and resulting coefficien...

Page 10: ...ach category is detailed separately in the following 5 3 2 Data Streaming The Data Streaming section allows the user to change settings that affect all three communication protocols and allows the use...

Page 11: ...ory Table 5 3 TCP Comms group settings 5 3 4 UDP Parameters The UDP section figure 5 5 holds all the settings specific to UDP In UDP mode each acquisition cycle of x number of channels is packed as a...

Page 12: ...whether an acknowledgement of these user commands is sent on the next higher message number Data may be transmitted on either multiple messages or alternatively on a single message ID with a selectab...

Page 13: ...16 bit unsigned calibrated decimal 16 bit unsigned and engineering units or voltage scaled to the known full scales Also for DTC scanners the temperature values as raw unsigned 16 bit and calibrated e...

Page 14: ...non temperature calibration may be performed at a single temperature Figure 5 9 shows the Calibration tab controls which are further explained in table 5 8 The Live values section is an indicator of...

Page 15: ...emperature calibration Unchecked only temperature point 1 is available to the user and the system will calculate coefficients for a non temperature calibration Live Values The live values of the curre...

Page 16: ...rol Function Range Shows the floating point value for the range contained within the scanner x3 derange Shows the floating point value for the sensitivity derange constant contained within the scanner...

Page 17: ...n data will remove single impulse noise events in the pressure data Temperature Input Impulse Filter As above but with temperature data Pressure input average samples Selects the number of samples for...

Page 18: ...TSEG1 TSEG2 SJW Register values for the CAN module within microDAQs microcontroller Table 5 9 Advanced communication settings 5 7 3 Miscellaneous The remaining parameters are edited via the Miscellan...

Page 19: ...AQ s internal calibration data table If I daq detected use raw calibration If checked this replaces the normal polynomial calibration function with a raw linear function whenever an I daq is present i...

Page 20: ...ear calibration Figure 5 12 Span and zero coefficients 5 9 Timestamp page This page allows the user to edit the timestamp settings of the microDAQ This timestamp will alow the user to get millisecond...

Page 21: ...the timestamp for every channel It should be noted that the latter 2 options will reduce the maximum transmission speed datastream get PC time This button allows the user to get the timestamp from the...

Page 22: ...ual basis and Chell Instruments Ltd Provides a fully traceable facility for this purpose 6 3 Adjustment There are no user adjustments in the instrument The user is strictly forbidden from removing the...

Page 23: ...uter Gnd 7 3 Can Connector Mating connector 9 way dtype male Pin Number Designation 2 CAN_L 5 Gnd 7 CAN_H 4 N C 5 0V 7 4 Trigger Connector Mating connector 50 Ohm BNC Pin Number Designation Center TTL...

Reviews: