refrigeration

Refrigeration teaching experiment remote lab

Current Testing Instructions:

Prerequisits

Python3
External modules used:
pyModbusTCP
numpy
I believe this was all that was nessissary to install to run the software on RPi Ubuntu

Setup

1. Ensure that testCommandServer.py HOST variable is set to loopback address 127.0.0.1 OR address of server host.
2. Ensure that testReportingServer.py HOST variable is set to loopback address 127.0.0.1 OR address of server host.
3. Ensure that commandClient.py HOST variable is set to same address as server
4. Ensure that reportingClient.py HOST variable is set to same address as server
5. If testing without hardware, ensure that simulate_hardware = True set in acUnitGlobals.py
6. Run testCommandServer.py and testReportingServer.py on host server
7. Run main.py on client server (raspberrypi/SBC in final implementation) It should connect to server with no issues

Operation

1. Enter commands as prompted in testCommandServer.py CLI. Track changes in state and function using CLI for main.py. view logfile during operation for debug messages, based on logging level set in init_logging in acUnitGlobals
2. Ensure that JSON messages reported by testReportingServer.py display "correct" values (if simulated hardware these values somewhat random and static at the moment

Issues

1. NOTE: 1st command sent from testCommandServer.py causes websocket to loose connection & reset. All commands after this should be handled normally.

Command Examples

{"cmd":"set","{item}":"{state}"}

{"cmd":"set","V1":"open"}
{"cmd":"set","V2":"open"}
{"cmd":"set","V3":"open"}
{"cmd":"set","V4":"open"}
{"cmd":"set","V5":"open"}
{"cmd":"set","V6":"open"}
{"cmd":"set","V7":"open"}

{"cmd":"set","V5":"open","V6":"open"}
{"cmd":"set","V5":"close","V6":"close"}

{"cmd":"set","V1":"close"}
{"cmd":"set","V2":"close"}
{"cmd":"set","V3":"close"}
{"cmd":"set","V4":"close"}
{"cmd":"set","V5":"close"}
{"cmd":"set","V6":"close"}
{"cmd":"set","V7":"close"}

{"cmd":"set","W1":"on"}
{"cmd":"set","W1":"off"}
{"cmd":"set","W2":"on"}
{"cmd":"set","W2":"off"}
{"cmd":"set","fans":"on"}
{"cmd":"set","fans":"off"}

{"cmd":"set","comp":"start"}
{"cmd":"set","comp":"stop"}

All the following words evaluate to True:
"open","opened","on","true","high","start"

All the following words evaluate to False:
"close","shut","closed","off","false","low","stop"
    

Future Commands

download CSV of all datapoints {"cmd":"get","item":"csv"}

safe shutdown {"cmd":"set","mode":"shutdown"}

run experiment with expansion valve Vx {"cmd":"set","mode":"V2"}

Development Notes

How to best handle exceptions / errors?

• Each function within a method should provide its own exception handling, and raise if exception is error
• Priority functions with known error conditions
• Priority on functions with known exceptions that are not errors
• If function is unlikely to cause exception then this is probably overkill.