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Can Powerlogic ION device provide timestamped Modbus data ?

Timestamps are not included in the Modbus protocol. The user would like to see timestamps for specific modbus registers directly from the device rather than the server. Power Monitoring expert, 3rd party OPC servers or 3rd party modbus servers will assign a timestamp based on the local system time when modbus communication occurs. 

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Powerlogic device with ION architecture

PME8 Designer, ION Setup

The example below shows how to include a timestamp for recorded the VLL average maximum value (Register 40187). The time stamp output will be in a UNIX format (defined as the number of seconds since January 1st, 1970, 0:00:00). This example can be replicated for any other Modbus parameters such as peak demand, maximum values etC. The diagram below describes the timestamp inserter mechanism.

1- The Store Module ( Tstamp VLL max) will store the current value whenever it’s triggered by Vll the maximum module. The latter will generate a pulse every time the variable VLL avg reaches a new maximum.
2- The Output of the store module is linked to a convert module to prevent “n/a” values. The convert module's output is linked to a modbus slave module.
3- There is no particular modbus module that you need to link to but the example above links the Vll time source to the Modbus Volts modules for convenience. Moreover, The Unix time value is a 10 digit value and a 32 Bit register is needed. 
4-To convert from UNIX time format to Microsoft time use the following formula: Microsoft time = (UNIX Time)/86400 + 25569
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