SMA Sunny Island 4248U, Installation & Operating Instructions Manual

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Installation SI4248U Manual
26
The maximum current that can be switched by either the load shed or generator request relay
differs a great deal depending on voltage and wether it’s AC or DC. The detailed load limit
curve is shown in the following graph.
Figure 1-13 Load Limit Curve for Load Shed and Generator Request Relays
Generator Run Confirmation
The Sunny Island 4248U has the ability to operate multi-wire start generators automatically
when used with the GenMan option (GenMan is an optional unit available from SMA
America). When the generator has been started, the GenMan will confirm operation by
sending a signal to these terminals. In this way, the Sunny Island 4248U can determine wether
the generator is functioning properly or not.
Terminal Function
SHIELD Shield
G_RUN - From Generator Ready negative output on optional GenMan unit
SHIELD Shield
G_RUN + From Generator Ready positive output on optional GenMan unit
Table 1-3: Generator Run Confirmation
0
V
olt
age [V]
50
0
100
200
Current [A]
270
6
250
300
0.1 0.2 0.3 0.4 0.5 0.7
1
0.6 0.8 0.9
2 4 3 5
DC resistive load
AC resistive load