Normal Operation; Operation At Excessively High Ambient Temperatures; Reaction To Too High/Too Low Temperature; Reaction To Excess Availability Of Power - Siemens SITOP solar User Manual

5.2 Normal Operation

This is the normal display on the MASTER. The speed of the running light also gives
you a quick idea of how much solar power is being fed in.
The microprocessor integrated in the MASTER now assumes control of the system
and the following tasks are performed.
• Either online data or stored operational data are output via the data
interface.
• A check is made to determine whether and with what power the connected
SLAVES are running.
• The display together with the push button are controlled.
• The running light is activated.
• The integrated data logger is updated with new data.

5.3 Operation at Excessively High Ambient Temperatures

When the maximum heat dissipater temperature of 43 degrees Celsius is exceeded,
a internally installed fan goes on to exhaust the heat loss. The switchoff point is 38
degrees Celsius. To ensure particularly low-noise operation, the speed of the fan is
adjusted proportionately to the temperature of the heat dissipater.

5.4 Reaction to Too High/Too Low Temperature

When the temperature of the heat sink exceeds 85 degrees Celsius, the power fed to
the power network is gradually reduced. At 100 degrees Celsius heat sink
temperature the power has reached zero.
With even higher temperatures, the device goes off with an error message.

5.5 Reaction to Excess Availability of Power

If the available power of the solar generator exceeds the maximum power of the
inverter, operation continues with maximum power without the output of an error
message.
Caution: The maximum possible power of your solar field will not destroy your device
but the highest no-load voltage under unfavorable conditions (cold and high
radiation) will!
5.6

Parallel Connection of Several Inverters

When several MASTERS are in parallel operation on a system, be sure that the
devices feed in at different phases to reach a balanced power-output distribution and
to reduce cross influence of the power monitoring systems (ENS).
The MASTERS are equipped with two serial interfaces. This permits simple
connection of the devices using a 9-pin standard RS 232 cable. A single cable from
the first device is the connection to the PC. To enable the PC to distinguish between
the inverters, a separate device address must be assigned to each MASTER of the
system. The assignment of the device address is done with the PC and the SITOP
solar log software. For more information, see the user's guide of SITOP solar log.
Siemens AG C98130-A7580-A1-1-7619
SITOP solar 08/2006
SITOP Solar D
Page 19 of 34