Lambrecht rain[e]H3, User Manual

Page: 46 / 59

User Manual
Precipitation Sensor rain[e]H3 with Ethernet
Id-No. 00.15184.540 020
rain[e]H3 Precipitation Sensor Manual
13.5 Read User Data
The user data is read out in the block (all 8 values) with the following command. Each value is returned in a
separate line with its own checksum per line.
Syntax:
<STX>COM:31<CR><LF>
Answer:
<STX>USR_MEM_ 1:abcdefghijklmnop<CR><LF>
1 = User data storage 1
2 = User data storage 2
3 = User data storage 3
4 = User data storage 4
5 = User data storage 5
6 = User data storage 6
7 = User data storage 7
8 = User data storage 8
13.6 Checksum
The checksum of a data telegram is calculated from the sum of all signs (alphanumeric signs and control codes
like STX until “*” but without the checksum bytes themselves). The control characters <CR> and <LF> that follow
the checksum are not part of the calculation.
The checksum will be calculated as follows:
1. From the sum the two’s complement is calculated
2. From the two’s complement the lower byte is considered
3. The upper and lower half-byte, changed to readable ACSII signs, are the checksum.
Example:
<STX>1234567890*C7<CR><LF>
<STX>1234567890* ist C7
13.7 Pulse Output
Each pulse corresponds to a predefined amount of measured precipitation. The resolution factor range is
0.01...200 mm per pulse. This resolution factor can be configured with the rain[e]H3 Commander along with the
closing time / pulse width. The duty cycle is 50%, in other words the closing time has the same length as the
pause time.
If more pulses have to be returned than possible with the given resolution and closing time, the remaining pulses
will be queued and returned as soon as there are no new pulses added. This means e. g. that if a closing time of
200 ms and a resolution factor of 0.01 is chosen - equivalent to 300 pulses per minute - and it is raining with an
intensity of 4 mm/min for two minutes and 1.9 mm/min thereafter - equivalent to 190 pulses per minute, the pulse
output will return 300 pulses in each of the first two minutes and another 200 pulses will be queued. In the third
minute again 300 pulses will be returned - 190 for the intensity in that minute and 110 from the queue. Accordingly
280 pulses will be returned in the fourth minute and 190 pulses in the following minutes, since there are no further
pulses left in the queue.
46