Procedure to send commands over Modbus to PM5000 Series.
Customer wants to send a command to a PM5000 to perform remote configuration or a meter reset.
Product Line:
PM5100 (PM5110)
PM5300 (PM5330, PM5340)
PM5500 (PM5560, PM5563)
Environment:
Remote meter configuration / resets
Resolution:
Step 1: Identify the Command Number and necessary Parameters
- Open the Modbus Register List
- Navigate to the Commands tab and locate the desired command
- Write down the Command Number and the Parameters
Table 1: Modbus Register List Excerpt |
Command Name | Command Number | Command Tag | Parameters |
Reset All Energies | 2020 | C_RESET_ALL_ENERGIES | (1) Command Semaphore |
Step 2: Get the Semaphore
- The Command Semaphore is stored in Modbus register 5680.
Note: Only perform the reading operation once. Doing more than once will cause in error. If by mistake the operation is performed more than one time then it is advised to try to do the operation again after 4 min.
Step 3: Sending the Command
1. Set register 5000 to the Command value
2. Set register 5001 to the Semaphore value
Register 5000 = 2020
Register 5001 = 62283
Registers 5002 - 5124 = not used for this command
- Then Click "Write"
Additional Information:
What commands are available?
A full list of the commands that can be sent to the PM5000 are detailed in the Modbus Register List under the Commands tab.
The table below lists several of the most common commands:
Warm Start Reset |
Set Date/Time |
Reset Cycle Count |
Reset All Min/Max |
Reset All Demands |
Reset Power Demand |
Reset All Peak Demands |
Reset Power Peak Demands |
Reset Input Metering Peak Demand |
Reset All Energies |
Reset All Accumulated Energies |
Reset Input Metering Accumulations |
Meter Initialization |
Acknowledge Alarms |
Disable Alarms |
Clear Data Log |
Reset Diagnostic Log |
What is a Semaphore and what is its purpose?
The semaphore is a number that is used to control write access to the PM5000. The semaphore can only be read once in a 4 min by a single master. Therefore, it is the only master that can send a command within the 4 min period. This process guarantees that the PM5000 is only receiving a command from one device at a time.
NOTE: The semaphore value which is received is valid for 4 minutes when not used, that is 4 minutes from the previous semaphore write.
For example: if the received semaphore value is used at the 3rd minute 30th second from when the value is received, then the same semaphore is valid for next 4 minutes.
You may use the semaphore value multiple times within that 4 minute window.
You will need to read the command semaphore again after 4 minutes from the previous read has elapsed in order to get the new number.