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BOARDJ
Users Manual
32 pgs716.75 Kb0

MadgeTech BOARDJ Users Manual

Operations Manual for RF Series
Data Loggers
MadgeTech, Inc.
Revised February 27, 2009
TABLE OF CONTENTS
INTRODUCTION ....................................................................................................... 3
TRANSMITTER CHARACTERISTICS .............................................................................. 3
TRANSMISSION DISTANCE ........................................................................................ 4
SYSTEM COMPONENTS AND SETUP ............................................................................ 4
WIRELESS CONFIGURATION DIALOG .......................................................................... 5
Transmitter Output Modes ...................................................................................... 6
Transmitter Options ............................................................................................... 6
Custom Transmit Interval ....................................................................................... 7
Indicator Mode ...................................................................................................... 9
REGISTERING THE DEVICE ON A SYSTEM.................................................................... 9
STARTING THE DEVICE AND SYNCHRONIZING THE TRANSMITTER ................................ 10
USING MULTIPLE DEVICES ...................................................................................... 12
PREVENTING COLLISIONS WITH PRIME NUMBERS ...................................................... 13
Prime Number Examples ...................................................................................... 15
AUTOSAVE OF WIRELESS DATA ............................................................................... 15
REAL TIME WIRELESS ALARMING ............................................................................. 17
SAVING ALARM SETUP TO XML FILE ......................................................................... 23
LOADING ALARM SETUP .......................................................................................... 23
INCREASING RANGE WITH THE RFEXTENDER ............................................................ 23
Simple RFExtender System ................................................................................... 24
Complex RFExtender System ................................................................................ 25
Module Address and Receiver Address Mask ............................................................ 25
Receiver Address Mask Example ............................................................................ 26
BATTERY LIFE ....................................................................................................... 28
OPERATING ENVIRONMENT ..................................................................................... 29
SYSTEM PERFORMANCE AND RELIABILITY ................................................................. 29
FCC COMPLIANCE AND REQUIREMENTS .................................................................... 31
FEDERAL COMMUNICATIONS COMMISSION (FCC) NOTICE ........................................... 31
INDUSTRY CANADA (IC) NOTICE .............................................................................. 32
CONTACT INFORMATION ......................................................................................... 32
TABLE OF FIGURES
Figure 1. Connecting the IFC110 interface cable ........................................................... 4
Figure 2. Connecting the RFC101A wireless receiver ...................................................... 5
Figure 3. The Wireless Configuration dialog .................................................................. 5
Figure 4. Start Device dialog ...................................................................................... 9
Figure 5. Delay Start Feature ................................................................................... 12
Figure 6. The Configure Wireless Data dialog ............................................................. 17
Figure 7. The Wireless Alarm Setup dialog ................................................................. 20
Figure 8. The Wireless Alarm Settings dialog – Notification and Channel tab ................... 21
Figure 9. The Wireless Alarm Settings dialog – Email tab ............................................. 22
Figure 10. The multi-alarm Wireless Alarm Notification dialog ....................................... 23
Figure 11. RFExtender as a wireless repeater ............................................................. 24
Figure 12. RFExtender as a wireless communication interface ....................................... 24
Figure 13. A complex RFExtender system .................................................................. 27
MadgeTech, Inc. Operations Manual for RF Series Data Loggers
INTRODUCTION
MadgeTech’s RF series line of wireless-enabled data loggers provides a simple, low-cost wireless solution for short-range data collection applications. These products are powered by a user-replaceable internal battery and can be configured for up to ten years of battery life. They are designed for one-way, low data-rate applications, and transmit real-time data directly to a PC for monitoring. Like MadgeTech’s standard series of data loggers, they are simple to use and their versatile configuration options allow for easy integration into a wide variety of applications. The product line includes models for all the most popular commercial and industrial measurements, as shown in this table:
PRODUCT DESCRIPTION RFTemp101A Temperature Recorder and Wireless Transmitter RFRHTemp101A Humidity / Temperature Recorder and Wireless Transmitter RFTC4000A Thermocouple Temperature Recorder and Wireless Transmitter RFRTDTemp101A RTD Temperature Recorder and Wireless Transmitter RFpHTemp101A pH / Temperature Recorder and Wireless Transmitter RFVolt101A DC Voltage Recorder and Wireless Transmitter RFProcess101A DC Current Recorder and Wireless Transmitter RFPulse101A RFOT
These products have onboard memory in addition to the wireless transmitter, so they can completely replace existing data loggers and strip chart recorders while providing an added wireless data link. This memory can also serve as a failsafe backup, in the event of interference in the wireless channel or interruption of service to the monitoring computer.
TRANSMITTER CHARACTERISTICS
Pulse Recorder and Wireless Transmitter Temperature Recorder and Wireless Transmitter
The transmitter used in the RF series products is a carrier present-carrier absent (CPCA) amplitude-modulated (AM) signal operating at a carrier frequency of 418 MHz. The data being transmitted is encoded similarly to standard RS232 serial data at a bit rate of 4,800 baud. This signal is detected by the RFC101A receiver module and converted to RS232 signals, which are passed to the COM port of the monitoring PC.
The transmitter type and encoding method permit the device to use the maximum allowable output power specified by the FCC, and also minimizes the amount of battery power required for the transmission. This gives the user the best possible range, and also ensures a long battery life.
To conform to FCC Part 15.21 rules, the data transmission takes less than one second and the minimum periodic transmission rate allowed by the device is 30 seconds. The low duty cycle permits several devices to use the same communication band and receiver without excessive interference caused by “talking over” each other.
TRANSMISSION DISTANCE
The transmission distance achievable with any wireless system is dependent on many factors. The only consistent measurement of transmission distance that can be used with these devices is called the “line-of-sight” transmission distance. The transmitter and receiver are set up in a large open area, free of obstacles and interference, and are aligned so their antennas are oriented in the same direction. Under these circumstances, the RF series products can achieve up to 120 feet (36 m) transmission range.
SYSTEM COMPONENTS AND SETUP
The following components are required to successfully set up and use the RF series products:
▪ A personal computer running the Windows operating system (Windows 95 or higher) ▪ One of the RF series wireless-enabled data loggers ▪ An RFC101A wireless receiver module and power supply, for receiving wireless
transmissions from the data logger
▪ An IFC110 interface cable, for communicating with the wireless data logger ▪ MadgeTech Data Recorder software, included with the RFC101A or IFC110
To configure the data logger, and register it on the PC for data reception, connect it to the PC through the IFC110 serial interface cable as shown in Figure 1 below.
Figure 1. Connecting the IFC110 interface cable
To set up the system for receiving wireless data, connect the RFC101A to the PC and plug in the power supply to a 110VAC outlet (as shown in Figure 2). In most cases, the IFC110 will need to be removed from the PC to connect the RFC101A. If there are multiple COM ports available on the PC, the RFC101A may be connected to a different COM port than the IFC110, thus leaving IFC110 connected. To switch between using the IFC110 and RFC101A, simply change to the appropriate COM port under the “Communications” menu.
Figure 2. Connecting the RFC101A wireless receiver
WIRELESS CONFIGURATION DIALOG
Figure 3. The Wireless Configuration dialog
The Wireless Configuration dialog (shown in Figure 3) allows the user to select from a variety of operating modes to meet the requirements of different monitoring systems. To access this dialog, identify the device using the Device -> Identify Device and Read Status menu item, switch to the “Device Detail” tab, and click the “Wireless Configuration” button. To edit the configuration, press the “Change” button in the dialog, make the appropriate changes, then press the “Save” button to commit the changes to the device. Note: Closing the dialog or exiting with the “OK” button will not store the changes in the device.
To comply with FCC regulations, saving a configuration change may cause the device to inhibit output from the transmitter while the internal timers synchronize to the new configuration (this may be the longer of the reading interval or custom transmit interval). To force synchronization of the timers and enable output before the aforementioned interval has passed; restart the device from the software.
Transmitter Output Modes
Real-time data transmissions may be sent through the RF antenna, the device’s serial port, both or neither. If both the serial and RF transmitters are disabled, the device will function strictly as a standard data logger. The typical user will configure the device for wireless transmission only thus transmitting data from the device to the RFC101A receiver. However, serial transmission may be desirable for some systems where the built-in transmitter is not powerful enough to maintain a reliable link, the signal must be brought outside of an environment that blocks RF, or when a hardwired connection to an alternate transmitter is required. Additionally, both modes may be enabled for combined local and long-distance monitoring of the signal. See “Increasing Range with the RFExtender” later in this manual.
Transmitter Options
The transmitter module has four configuration options. Two of these options pertain to enabling and disabling the transmitter under different operating conditions and two pertain to the timing and format of the transmitted signal. These options are summarized below.
1. Transmit only while logging – If this option is selected, the transmitter will only
output data when the logger is recording data to memory. When memory is filled and the device stops logging, the transmitter will stop as well to indicate the logger needs to be offloaded and restarted. If the memory wrap-around mode of the logger is enabled, the device will continue to overwrite the oldest internal data and continue transmitting data wirelessly. If this transmitter option is not selected, the transmitter will continue to operate regardless of whether the device is recording data.
2. Transmit under switch control – If this option is selected, the on/off switch may
be used to inhibit the transmitter output. This allows the user to manually stop the transmitter without affecting the logger operation or transmission timing. This may be useful for transporting the device through an area where other devices are operating on the same frequency band, disabling the transmitter until the device is placed in-system, or disabling individual devices to evaluate system performance and troubleshoot interference or collisions. In systems where a manual override is not desirable, this option may be left unchecked, and the transmitter will not be affected by the position of the switch.
Note: The above two transmitter options function as such: if either one of the
modes would disable the transmitter under given conditions, the transmitter will be
disabled. For the transmitter to be enabled, the required conditions must be met for both options to allow the transmission.
3. Randomize transmit interval – If this option is selected, the transmitter will wait a
short random delay of up to 5 seconds before it transmits each data packet. This can decrease the chances of lost packets due to devices “talking over” each other because of long-term timer drift. Devices that are initially synchronized to transmit 10 seconds apart can drift in their timekeeping by up to 2 seconds per day, meaning that they could potentially interfere with each other after a few days of sustained operation. Because the transmission lasts less than a second, a random delay of up to 5 seconds can allow the majority of the transmissions to escape interference. If this transmitter option is not selected, the device will transmit at the interval set by its timer to within a few milliseconds. It is then up to the user to make any necessary accommodations for the timer drift. See “Using Multiple Devices” later in this manual.
4. Use error correction – If this option is selected, the transmitter output format will
be modified to include a simple forward error correction scheme known as a Hamming code. This method of error correction allows the receiver in a one-way transmission to correct any single bit error in each block of eight data bits being received. This option may help to increase system reliability in some environments.
Note: System reliability will most commonly be degraded by loss of signal or by burst noise longer than a single bit, thus this option may not substantially improve performance for the typical user. Additionally, if this option is not selected, the device may be able to transmit two complete copies of the data packet, increasing the likelihood that one of the copies will be received even when the other is lost due to interference. (Each packet always contains error detection, to ensure that invalid data is not displayed.)
Custom Transmit Interval
By default, the transmitter module will transmit a data packet with each internally recorded data point, or if it is not recording, at the reading rate specified for the data logger. This option allows the user to specify a custom transmit interval that will be used only by the transmitter. Like the data logger reading rate, this interval is limited to a minimum of 30 seconds and a maximum of 12 hours, but unlike the reading rate it may be set to any multiple of 10 seconds. Additionally, the device can be configured to return new data every interval, or to repeatedly send the data from the most recent internally recorded reading. This option can be useful for the following reasons:
1. Real-time monitoring – Some applications may require relatively quick feedback of
trend data to the user, but only need to be recorded at longer intervals. With this option, for example, an operator could check the trend of a system every 10 minutes and make necessary adjustments to keep the system within specifications, but the official logger record of the data only needs to indicate the value on an hourly basis.
2. Increasing system reliability – In applications where the operating environment is
unfriendly to RF, this option can be used to repeat the same data multiple times to increase the probability of successful reception. If the logger is recording every 5 minutes, the transmitter can be configured to send the data from the last reading every 30 seconds, allowing for 10 transmissions per logger reading. If the
environment sees a burst of RF interference a few times per minute, it is highly probable that one or more transmissions will be received properly.
3. Staggering transmissions from multiple devices – If several devices need to
record data at the same time while transmitting the output in real time, this option can be used to ensure that at least one transmission from each device is sent without interference from the other devices. This is similar to the randomization option provided above, but is better suited to some applications. See “Using Multiple Devices” later in this manual. In the screenshot below, this particular wireless data logger is set to “delay start” at 1:00PM; since the sample interval is 30 seconds, the next data logger should be started at 1:00:30, and the next logger should be started at 1:01:00, and so on.
To prevent confusion, it’s helpful to set a delay start time for the first logger that is on the hour, half hour, quarter hour, 10 minutes of, and 5 minutes of. For example:
On the hour: 2:00PM, 3PM, etc. On the half hour: 2:30PM, 3:30PM, etc. On the quarter hour: 2:15PM, 3:15PM, etc. 10 minutes of: 2:50, 3:50, etc. 5 minutes of: 2:55, 3:55, etc.
To find the ideal delay start interval, use the following calculation:
To determine the reading rate, you must perform a simple calculation: X/Y=Z. To solve for the ideal reading rate (Z), divide X by Y.
Desired Reading Rate(X) # Of Loggers(Y) = Ideal delay between loggers (Z)
Example: 15 minutes X 60 seconds 25 = 36. It is best to use the closest odd number, so a 37 second delay start interval will be used.
Note. Rounding up is not encouraged because it can increase the chances of data overlap.
X= Desired reading rate (in seconds) Y= # of loggers Z=?
Example 1:
If X= 15 minutes, and Y= 25 loggers, then Z= 0.6 minutes X 60 seconds = 36. In this example, 36 is rounded to an odd number, such as 37; 37 seconds is the ideal delay start interval. Example 2:
If X= 60 minutes, and Y = 75 loggers, then Z= 0.8 minutes X 60 seconds = 48. In this example, 48 is rounded to the nearest odd number, such as 49; 49 seconds is the ideal delay start interval.
Note. If Z results in < 30 seconds, change X and/or Y.
Figure 4. Start Device dialog
Indicator Mode (not applicable to the RFOT)
The device may be configured to blink the LED activity indicator every 10 seconds (the factory default setting) or only when a scheduled reading is taken. The green LED indicator will blink to indicate that the device is configured properly to allow a wireless transmission to occur. If the wireless transmitter is disabled by any of the available configuration options (by setting the transmitter output mode to disable the wireless output, or by selecting either of the related transmitter control options), the indicator will not blink. When a wireless transmission is about to be sent, both the green and the red LED indicators will blink.
The primary reason to turn off the 10-second indicator is to conserve battery capacity. See “Battery Life” later in this manual. The 10-second mode is forced “on” if the custom transmit interval discussed above is enabled.
REGISTERING THE DEVICE ON A SYSTEM
Before the MadgeTech software will receive data from an RF-series transmitter, the device must be properly registered on the system. When the device is identified or configured, the PC software will store an image of the device for future reference. This image is stored on the PC’s hard disk so it is retained even when the software or PC is shut down. The software then refers to the device image when receiving a transmission to “fill in”
the information that is not transmitted in the data packet. This information includes the device ID, calibration date, and measurement variables such as a thermocouple type or engineering units. The data packet contains a checksum of critical settings to ensure invalid data is not displayed. For this reason, the device must be re-registered if it is calibrated or the measurement data is changed on another PC. Note that re-registering a device after a configuration change will not allow the PC to receive data from the transmitter if there is already data from the device in the wireless graph. If no data has been received since the software was launched, or the software is closed and launched again, the software will receive the transmissions as expected. This behavior is caused by the fact the data that has already been received is only valid with the previous image. Adding new data to the old dataset with different calibration constants or
thermocouple type would result in invalid data.
STARTING THE DEVICE AND SYNCHRONIZING THE TRANSMITTER
Like other MadgeTech data loggers, the RF series devices must be configured through a PC. The wireless transmitter is primarily set up through the “Wireless Configuration” dialog discussed previously, but synchronization of the transmitter to the desired starting time is accomplished through the “Start Device” dialog when launching the data logger. When launching, choose the start time, and set the logger parameters (device ID and reading rate) for the run. When the device is started, both the logger and transmitter time base will be set for the selected start time. They will remain inactive until the selected time, and then begin to operate as configured in the “Start Device” and “Wireless Configuration” dialogs. When the delay-start time arrives, the logger will take readings (if enabled) at the programmed reading rate, and wireless transmissions (if enabled) will be made at the reading rate or custom interval, depending on how the device is configured.
If a delayed start is specified, the device will remain completely inactive during the start delay period. The indicators will not blink, no readings will be taken and no transmissions will be sent. It will continue to communicate normally, and may be queried, stopped, or restarted. If the application only requires the wireless transmitter without data logging capability, the device may be stopped immediately (when the “Transmit only while logging” option is not selected) after launching without affecting the scheduled start of the wireless transmissions. This will marginally improve the battery life when data logging capability is not required.
If immediate start is specified, the device will begin logging immediately, but it will inhibit transmitter output for the first reading to comply with FCC regulations. To ensure the first transmission is sent, use the delayed start mode with a 1-2 minute delay (minimum allowed by software).
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