Milltronics InterRanger IR-200, Инструкция по эксплуатации

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InterRanger IR-200 44 PL-545
The following values are defined for this field:
1: Feet from bottom to top
2: Meters from bottom to top
3: Feet from top to bottom
4: Meters from top to bottom
5: Percentage of tank depth
The trigger point bits specify the value of the TRIGGER POINT program parameter. This value ranges from 1
to 6.
The profile averaging time field of the message specifies the time over which the tank profile is generated. It is
specified in minutes.
The tank depth field of the message specifies the programmed tank depth. For instrument scales in feet and
percentage of tank depth, the tank depth is specified in tenths of feet. That is, if the tank depth is 12.3 feet, it
is transmitted as 123 decimal or $007B. For instrument scales in meters, the tank depth is transmitted in
hundredths of meters. A tank depth of 2.62 meters would be transmitted as 262 decimal or $0106.
The current interface level is transmitted in the interface level field of the message. For instrument scales in
feet, the interface level is transmitted in tenths of feet. For instrument scales in meters, the interface level is
transmitted in hundredths of meters. For the percentage of tank depth scale, the interface level is transmitted
in percent. That is, if the interface was at 50% of the tank depth, it would be transmitted as 50 decimal or
$0032. The interface level will be transmitted as $0000 if any errors were encountered while measuring the
blanket level.
The transmitter power level is a value between 0 and 100 (decimal) which indicates the power being used to
generate profiles. This information is useful when comparing profiles or troubleshooting.
TANK PROFILE
A Tank Profile message is transmitted by the IR-200 in response to a Request Tank Profile message
transmitted by the host computer. The tank profile indicates the strength of the return signal at various depths
in the tank.
The message is formatted as follows:
Data Length: $FA
Message Type: $82
Additional Data: $02 – $FA: Tank profile
$FB: Transmitter Power (AGC level)
$FC: Resolution/Max depth
$FD: MSB – speed of sound factor
$FE: LSB – speed of sound factor
The tank profile consists of 249 samples. Each sample is an unsigned byte value which corresponds to the
relative signal strength of the return echo at a particular depth. In normal situations, the samples are spaced
0.1 feet apart. The first sample corresponds to the signal strength 0.1 feet below the surface. The 249th
sample corresponds to the signal strength 24.9 feet below the surface. This sample resolution changes if the
tank depth is greater than 25 feet. Byte $FC of this message is normally set to a value of 1. This setting yields
the standard 0.1 foot resolution (or spacing) between profile sample points and the corresponding maximum
depth of 24.9 feet. If byte $FC of this message is equal to 2, then the spacing between sample points will be
0.2 feet. There will still be 249 total points, so the maximum depth will now be 49.8 feet. Likewise, byte $FC
may be set to a value of 3 or 4, yielding resolutions of 0.3 and 0.4 feet, respectively.