Safety Measures; Electronic Short Circuit Safety; Hardware Safety; Safety Features - opti-solar SC-Max series User Manual

8 Safety Measures

We urgently recommend the installation of a safety device on the battery pole in order to prevent damage from
short circuits between battery and the solar charge controller.

8.1 Electronic Short Circuit Safety

An electronic short circuit safety device is built into the solar charge controller and prevents both destruction of
the solar charge controller and the blowing of the safety fuse in case of short circuits on the load terminals. The
second line of the LCD display indicates this error as "Short circuit". After elimination of this fault, the solar charge
controller automatically switches back to normal operation after about 60 seconds.

8.2 Hardware Safety

In addition to the electronic fuse device mentioned above, the solar charge controller has also been protected
by regular fuses which have been rated far beyond nominal currents to prevent false blowing of the fuses during
surges. The safety fuses are wired in parallel. In order to prevent fuses from blowing in the case of high currents
over a short period of time, a high value has been selected. Before the fuses blow, the electronic safety fuse
should prevent any excessive current flow.

8.3 Safety Features

Reverse polarity
Short circuit
Over current
Reverse Current
Over voltage
Low voltage
Over temp
*1 Controller can not protect itself in a 24V system when polarity of battery or solar is reversed.
*2 Controller can protect itself, but loads might be damaged.
*3 Battery must be protected by fuse, or battery will be permanently damaged.
*4 The solar panel voltage should not exceed this limit for a long time as voltage protection is done by a
varistor.
Warning: The combination of different error conditions may cause damage to the controller.
Always remove the error before you continue connecting the controller.
Solar terminal
Protected *1
Protected
Protected
Max. 55V *4
switches off the load if the temperature reaches the set value
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Battery terminal
Protected *1
Switches off immediately
Protected *3
Switches off with delay
Max. 40V
Load terminal
Protected *2
Switches off