String Combiner Box


The String Combiner Boxes of RaychemRPG in technical collaboration with Fimer are intelligent control boxes (SMART) which allow the measurement of the current of each input PV string from the solar generator and allow the creation of the parallel output of all the strings of PV modules connected to them.

This high-performance device implement the current measurement using Hall Effect transducers and ensure an accurate localization of the malfunction of the PV field thereby minimizing the production downtime and facilitating the timely and targeted intervention of service. Each String Box is equipped with protections against overvoltage, implemented by SPD varistors, the switch in input is implemented by the fuse holders and in output by a switch; these devices allow to isolate the single sub-field PV or the individual strings from the solar generator, allowing operators to work safely.

Through these advanced technology product, customer can also manage the complete control and monitoring of the PV field. The monitoring of the unbalance currents (miss-matching) is built and available within the control logic of our inverters. Thanks to the String Combiner Box, it is possible to control the solar installation using the integrated modbus rtu protocol, and in this way it’s compatible with the most diffused communication systems in the market.

Technical Data of SBC24

Output Switch
Typology Rotary switch 1000 VDC (Note1)
Connection mode Unprotected terminals
Operating class DC21
Max voltage (VDC) 1000 V
Max current (ADC) 250 A
Input Fuse Holders
Typology Fuse holder type 10×38 GPV
Max voltage (VDC) 1000 V
Max current (ADC) 32 A
N° of DC+ input 24
N° of DC- input 24
Typology Cylindric 10×38 GPV
Max voltage (VDC) 1000 V
Max current (ADC) To be defined during the order (up to 30 A)
N° fuse 48
DC Surge Protection
Typology Class 2 SPD (varistor type Y)
Operating voltage (VDC) 1000 V
Strings Current Monitoring
N° of input strings 24
Max voltage (VDC) 1000 V
Max current (ADC) 25 A
Methode of measurement Using Hall effect probes
Voltage Control Strings
Max voltage (VOC) 1000 V
General Data
Auxlialry AC Power supply Stabilized power supply 230 VAC/24 VCC 15W
Communication port-protocol RS485 – MODBUS RTU Protocol
Safety class II
Accuracy 0.5% f.s.
Dimensions (DxWxH mm) 550x270x700
Weight 25.5 Kg
Colour RAL 7035
External protection degree IP65
Internal protection degree IP20
Operating temperature -20 / +50 C°
Height above the sea (Note 2) up to 2000 m
Installation Vertical wall mounting, by means of fixing brackets
Box and back plate material Fyber glass reinforced by polyester / Galvanized metal sheet / Fibra di vetro rinforzata in poliestere / Lamiera zincata
Door / openig angle / lock Blind /> 120 ° / Standard
Cables input-output By cable gland
SCB Series Uploaded 03.04.2015 Download