Ammonia refrigerator control by inverter

[torranin]

Hello, Tycho & Josip,

Thank you very much for your advise.
I just come back from Chinese New Year Holiday.

About your advise for start/stop peroids,
I still do not understand clearly.
May I confirm my understanding.

- Close all solenoid valves when we start compressor
- Run compressor at min speed until oil pressure up to normal operation level.
-open solenoid valve one by one until all open.
- motor speed control by temp control loop.

Is it correct?

By the way, I still do not understand clearly about the reason why.
I guess because of energy saving purpose. is it correct?

[Tycho]

Hello, Tycho & Josip,

- Close all solenoid valves when we start compressor
- Run compressor at min speed until oil pressure up to normal operation level.
-open solenoid valve one by one until all open.
- motor speed control by temp control loop.

Is it correct?

By the way, I still do not understand clearly about the reason why.
I guess because of energy saving purpose. is it correct?

When you start the compressor, start it in 0% capacity, when the compressor has minimum speed and has oil pressure, start increasing capacity step by step.

when the compressor has 100% capacity, start increasing speed, step by step.

this should be controlled by a pressure sensor connected to the low pressure liquid tank)

with this system, you can have the suction pressure at 0.1 bar, and you wont get any jumps in suction pressure when the compressor goes down in capacity.

when the compressor is at low speed and minimum capacity, the performance is so low that even a small load on the system can keep the compressor running.
This helps you keep a very stable low temp, compared to if the compressor stop on low pressure and you have to wait for the pressure to go up before it starts again.

How is the weather in Thailand now? I'm going to Phayakkhaphum Phisai in one and a half week

[torranin]

Hi, Tycho,

About Phayakkhaphum Phisai (Maha Sarakham Province) weather,
I found temp. around 14-33 Deg C and cloudy.
It may raining soon as Bangkok which raining everyday.
The 21st of this month, Thailand will have Makha Bucha holiday. a day relate to buddhism.
At North-earthern of Thailand (Rural area), they will has some activities like carnival. people will go to temple to pray the buddha and monk.

TKs
Torranin K.