Barometer/Humidity Sensor

Barometer/Humidity Sensor

1

Vaisala

PTU300

Serial Interface Cable

1

Vaisala

19446ZZ

RS-232 to Ethernet Adapter

1

Lantronix

UDS2100

This is the version with two serial ports (but standard 9-pin RS-232 connectors)

Read pressure value

Value reported as telemetry (see below)

Read temperature value

Value reported as telemetry (see below)

Read relative humidity value

Value reported as telemetry (see below)

Build

Observing

Maintenance

Pressure measurement frequency

Yes

No

Maybe

Set in configuration file. If this needs to be changed, edit configuration file, re-install, and then restart dispatcher.

Temperature measurement frequency

Yes

No

Maybe

See pressure.

Relative humidity measurement frequency

Yes

No

Maybe

See pressure.

Pressure measurement

Once every 5 sec [TBC]

Environmental monitoring

Managed through configuration file

Temperature measurement

Once every 5 sec [TBC]

Environmental monitoring

See pressure.

Relative humidity measurement

Once every 5 sec [TBC]

Environmental monitoring

See pressure.

Time of last connection

More than 10 seconds

Vaisala PTU300 User’s Guide (2019 version; device purchased in 2014)

https://www.vaisala.com/en/products/instruments-sensors-and-other-measurement-devices/instruments-industrial-measurements/ptu300

Lantronix UDS 2100 Quick Start Guide

https://www.lantronix.com/products/uds2100/#tab-docs-downloads

Lantronix UDS 2100 User Guide

https://www.lantronix.com/products/uds2100/#tab-docs-downlo

Python 2 software written by a student some years back. These lines of code were used to read values from the Vaisala while it was installed at Keck.

That installation was using a USB interface on a Windows machine. Not sure if the current serial interface will change anything here.

As part of the KROOT distribution, there is a SerialStream interface which manages connections to and from serial hosts. This includes managing Lantronix connections.

VAISALA_CONN

On or Off - controls whether or not the connection to the Lantronix is on or off.

Can be used if the Vaisala needs to be unplugged and moved, for example.

Boolean which is writable.

VAISALA_IP

IP address of the Lantronix box.

String set in the configuration file, only readable.

VAISALA_PORT

Port for the Lantronix box that talks to the correct serial device.

String set in configuration file, only readable.

VAISALA_RETVAL

Value returned by Vaisala.

String. The format is set in the configuration file. Only readable.

VAISALA_TIME

Time stamp of when the last RETVAL was received.

Unix timestamp (binary) or time stamp (ascii). Only readable.

VAISALA_PRES

Pressure value in units of hPa.

Double value from RETVAL, read only.

VAISALA_RH

Relative humidity in %.

Double value from RETVAL, read only.

VAISALA_TEMP

Temperature in deg C.

Double value from RETVAL, read only.

DISPSTA

Dispatcher status.

Enum and read only. If value is 4 or “Not Connected” the connection to the Vaisala or the Lantonix is not available. If value is 3 or “Connecting” the dispatcher is attempting to connect to the Vaisala through the Lantronix.

prefix

Vaisala

Prefix of the keyword names. If this is going to be changed, needs to be changed in XML directory as well.

ip

192.168.23.102

IP address of the Lantronix box.

port

10001

Port that is used for Vaisala, this is port 1.

format_str

form 9.4 "P=" P " " U6 6.4 "T=" T " " U3 6.4 "RH=" RH " " U4 \r \n

Format statement of the output from the Vaisala. At dispatcher start up and at every new connection, this value is sent to the Vaisala. The #.# sets the number of characters (first # ) and the second # sets the number of characters after the decimal point. There must be a space between the characters that notes what the value is (such as P=) and the actual value (the P). The code uses the characters (P=, RH= or T=) to determine what the next value is.

poll_time

5

Time between reads of the Vaisala in seconds.