BLOGR24 OPERATIONS

The BLOGR24 normally operates in RS232 console mode. (It may be switched to RS485 console mode by moving the Power/Comms cable from connector P11 to P12 and using a suitable RS485 converter with your PC - see RS485 note below as well).

Refer to MET BLOGR24 Commands - NTAS with SDHC and external Iridium Support for full command descriptions.

Getting Started

• The following equipment should be available:
  • Computer running a terminal program (ProComm Plus or HyperTerm) with RS232 output set for 9600, N, 8, 1.
    Run with caps-lock ON.
  • Power supply with output of 12-15 vdc and capacity of 100 ma. Make sure that the polarity is correct otherwise the BLOGR24 may be damaged!. A meter in series with the LOGR53 power supply is recommended to monitor the supply current (less than 10 MA is typical after the sign-on message has been sent if no MET instruments are connected).
  • If the BLOGR24 logger housing is open, use the RS232 adapter cable to connect from a DB9 Male RS232 on your PC to the 4-pin Molex that terminates the standard BLOGR24 power/comms cable. This adapter includes a 2-pin Molex connector can mate to a standard BLOGR24 battery or power supply adapter cable. Otherwise, use an SAE adapter cable to connect from the console SAE bulkhead connector to the RS232 adapter cable.

• Make sure the power supply is OFF.

• Hook up everything, start the terminal program and get it set for the correct COM port and 9600 baud, N, 8, 1 operation.

• Power up and check for power consumption of less than 50 MA at outset. Within a few seconds, you'll see a sign-on message, and once the "Running" message appears (up to 15 seconds after the initial message), the current consumption typically drops to about 10 MA with the supply set for about 13.5 VDC if no ASIMET modules are attached. Idle current WITH ASIMET modules will be around 30 MA with miscellaneous peaks during individual module internal activities, and at the top of each minute as the BLOGR24 polls each module for new data.

Individual ASIMET modules may be connected and disconnected while the BLOGR24 logger is running. Each minute, as modules are polled, missing modules are flagged, and the STAT command will report comms failures during all but the final 15 seconds of the logging interval (see RI setting, typically 60 seconds). For example, if there is no response from the PRC module when the BLOGR24 logger polls, the STAT command will report "PRC failure" in its output message for the next 45 seconds; power to the module is also turned OFF during this time, and 15 seconds before the end of the interval, it is restored. Hopefully the module recovers for this next cycle; note that modules DO NOT produce "good" data values until they rollover their internal 60-second sampling intervals; thus, for example, a WND module will respond the first minute after it is connected to the BLOGR24 logger (so there will be no failure message for the next minute) but will not have good data until the next minute. This is normal; ALL ASIMET modules operate asynchronously on their individual internal real-time clocks.

Communications

The BLOGR24 (like ASIMET) has a communications protocol based on the SAIL (Serial ASCII Interface Loop) protocol developed at Oregon State University. The module is interrogated by sending commands with the following format (always with capital letters and terminated with a RETURN <cr>):

#STAT<cr>

The STAT or STATD command will display several lines of status info about the instrument. Note that unlike the ASIMET and VMCM2 series instruments, the BLOGR24 software does not use SAIL Addresses currently, just the preceding # character, and always a terminating RETURN (ASCII carriage return <cr>)

On power up, the BLOGR24 logger will always come up running and logging as last configured (the STAT or STATD command will indicate Sampling GO when the BLOGR24 logger is running).

NOTE that only a subset of the commands is available while the LOGR53 logger is running. The H command will indicate which commands are available depending upon the GO / STOPPED state of the BLOGR24 logger.

Refer to MET BLOGR24 Commands document for full command descriptions.

Deployment Quick Start

For the complete discussion of BLOGR24 system preparation for deployment, refer to the LOGR53-CF System Prep document.   While this document refers to the older LOGR53-CF logger, most of the information is valid, since the BLOGR24 is a drop-in replacement for the older logger.

The important steps are:

• Check the basic operation of the system.
  • Startup looks normal on the attached PC/terminal.
  • After a minute (RI set to 60 seconds), D and E commands give reasonable results from the MET modules.
  • With Sampling STOPPED, T commands give reasonable results.

• Set the clock if necessary (CLOCK command).

• Initialize the SD Card if needed or Erase the DATA file, then check that everything looks OK.
  • SDOK commands to access SD Card.

• Be sure everything returned by the STAT or STATD command looks correct - especially Sampling GO if you are already running on the deployment batteries!!!

• The deployment batteries are NEW batteries, right?

• NOTE: If you did a complete deployment prep per the LOGR53-CF System Prep document, you can wait to connect the deployment batteries until shortly before deploying the BLOGR24 system; Remember that the BLOGR24 logger will ALWAYS power up RUNNING and LOGGING to the SD Card.

• Seal up the BLOGR24 logger and go....

RS232 to RS485 converters

• 2012 - This info may be obsolete! Original info pre-2007.

• Black Box, Inc. sells 2 converters that work well. The first is a PCMCIA/RS485 port (Part# IC114A, $199). This unit works well on laptops with PCMCIA slots but does not suppress the transmissions (you see two sets of what happens).

• The second is a standalone unit (Part# IC108A, $259). This unit works well on the bench.

  The settings for the IC108A standalone unit are as follows (* indicates default):

  
    
  XW1A		DCE * 
    
  W8		B-C	2-wire
    
  W15		A-B * RTS/CD enabled
    
  W5		A-B *  RTS/CTS delay normal
    
  W9		RTS/TCS delay	C*	0 msec
    
  W17		D	0.7 msec	time driver remains enabled after a low-to-hi transition
    
  W16		B * 	0.1 msec	Turnaround delay
    
  S1		OUT * 	Normal
    
  S2		OFF *		RS-485 receiver Unterminated
    
  S3		OFF *		Line Bias Off
    
  TB1:
    
     term 1, Rx	B+ (connect to 3, Tx, B+) to the +485 (orange)
    
     term 2, Rx	A-  (connect to 4, Tx, A-)  to the -485 (brown)
    
     term 3		Tx	B+
    
     term 4		Tx	A-
  
  

• An RS485 adapter cable connects from a DB25 Male RS232 on the Black Box IC108A to the 4-pin Molex that terminates the standard LOGR53 power/comms cable. This adapter includes a 2-pin Molex connector can mate to a standard LOGR53 battery or power supply adapter cable.