Question
After running a TARE command on my Hardy PLC module, my system loses power. When it powers back up, the Net weight is a different value than when it lost power. What is happening and how do I prevent the loss of my Net reference point?
Answer
When you run a TARE command on a Hardy PLC module the unit will write the current Gross weight reading into the Tare Value. The Net weight is the result of the current Gross weight minus the current Tare Value.
If you lose power to the system after running the TARE command you will lose the new Tare Value. This is because the unit will not automatically do a save of this change in values. Normally after a period of time, if no new Tare command is given, the unit will save this new value. To save it every time a tare command is sent could cause the unit to write to the memory so often that it wears out the memory chip. These chips only have so many writes available to them before they can no longer save the change.
To prevent this loss of your Net weight reference, you can trigger a Save command after you run the Tare command. This will force a save of the new reference and you will not lose this with a power cycle. Be aware that if you Save frequently you will be shortening the life of the memory chip.
