5 connecting the load resistor, Connecting the load resistor – SMA WBP-Box User Manual
Page 17
SMA Solar Technology AG
5 Electrical Connection
Installation Guide
WBP-Box-IEN103320
17
5.5 Connecting the Load Resistor
Requirements:
☐ Load resistor never exceeds 54 Ω at the operating temperature.
☐ Load resistor never drops below 30 Ω when switched off.
☐ Load resistor has been designed for the maximum voltage of the Windy Boy Protection Box.
☐ The heat from the load resistor is permanently conducted away.
Cable sizing:
☐ Cable of type "RADOX GKW - LW/S 3x2.5 mm²" or a comparable cable used.
☐ Maximum length is 3 m.
☐ Maximum cross section is 6 mm².
1. Measure the resistance of the load resistor.
☑ The resistance is above 30 Ω .
✖ The resistance is below 30 Ω ?
The load resistor is not suitable for connection to the Windy Boy Protection Box.
• Select another load resistor. Observe the requirements when doing so.
2. Attach the M20 cable gland to the enclosure opening for the load resistor.
3. Unscrew the cable gland's lock nut and pass it over the cable.
4. Connect PE to the PE connection terminal.
5. Connect the cable shield to the PE connection terminal.
6. Connect LR+ to the LR+ connection terminal.
7. Connect LR − to the LR − connection terminal.
8. Tighten the lock nut firmly to the cable gland.