EATON xChargeIn UDP Programmers Guide V 2.01
EATON xChargeIn, UDP Programmers Guide V 2.01
9
© EATON 2018
2.5
Current control
Please note that AC (alternating current) charging stations do not control/
change the charging current directly. AC charging stations use a PWM
(pulse width modulation) signal to communicate the maximum allowed
charging current to the vehicle as specified in IEC 61851-1. All xChargeIn
are AC charging stations. The actual current is solely controlled by the
vehicle. If the wording used in this document indicates a current change, the
actual meaning is always a change in the maximum allowable current
(target current) communicated to the vehicle.
xChargeIn complies with IEC 61851-1. This international standard requires a
minimum waiting time between two consecutive current changes. To fulfill
this requirement, all xChargeIn will delay the execution of UDP commands
requesting a current change during a charging session. The affected
commands are
currtime
and
curr
. The request to stop charging via
currtime 0 1
will not be delayed and executed as soon as possible.
When a command, either
currtime
or
curr
,
sets a new value for “Curr user”
the device prepares to change the target current within the next 6-7 seconds.
If another current change is requested via UDP command during this period
of time the target current will be overwritten but the timer will not reset. The
following examples illustrate the system behavior:
Example 1
10:07:19
curr
command changes the value of “Curr user” immediately.
10:07:19
Internal timer starts at the same moment.
10:07:25
The change in the target current is executed and the
value of “Max curr” is
changed.
Example 2
09:46:09
The first
currtime
command initiates a change of the target current.
09:46:10
The field “Curr user” is updated and the internal timer starts.
09:46:11
The second
currtime
requests another current adaptation.
09:46:12
The field “Curr user” is updated again but the internal timer is already running.
09:46:16
The change in the target current is executed and the value of “Max curr” is
changed to the value sent by the last command.
