LEM DCBM 400 Series, Operation Manual

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21January2021/Version 0
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7.2.2. Conditions to start and input parameters
Prerequisites to a start command are:
• (1) The Meter Unit and Sensor Unit are mounted as per LEM instructions
• (2) There is no fatal error raised
• (3) There is no running transaction
• (4) Time synchronization is valid
In the device, this corresponds to the following values:
Table 6: Transaction preconditions in device implementation
If those conditions are met, a start request on /legal API (see §7.1) initiates a transaction.
Minimum duration for transactions is 2 minutes, to prevent potential memory storage weaknesses.
The start request shall include the following inputs:
Input name Type Designates...
evseId
Character string, max 37 bytes-long the EVSE in which the DCBM is located
transactionId
Character string, non-void and max 37 bytes-long the transaction (from the backend)
clientId
Character string, max 37 bytes-long the end user
tariffId
Integer from 0 to 4 the tariff used
cableId
Integer from 0 to 7 the cable loss compensation level to use
userData
Character string, max 128 bytes-long a contract reference, or any other extra data
Table 7: Required inputs to a new transaction
Below is an example of request body to start a transaction.
Figure 41: Example of body for start request
Above index Parameter name Value for readiness to new transaction
(1) suLinkStatusIsOk True
(2) muFatalErrorOccured False
(3) transactionIsOnGoing False
(4) timeSyncStatusIsOk True
!
{
"evseId" : "evse15674",
"transactionId" : "transac5765",
"clientId" : "client44678",
"tariffId" : 2,
"cableId" : 1,
"userData" : "Test of a transaction"
}