Pronto Energy 
How to Select a DC Combiner Box for Rooftop PV Strings
How installers size string inputs, fuse protection and enclosure ratings when specifying a 1000 V DC combiner box for rooftop photovoltaic arrays.
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Low-voltage protection for distribution boards and photovoltaic systems, plus related accessories.
Sourcing & SupportMiniature Circuit BreakersOvercurrent protection for AC boards and DC PV circuits.All Products
32–63A MCB 3P 3kA Type B/C/D KNB1-63 Korlen
32–63A Mini Circuit Breaker 2P 10kA Type B/C/D KNB2-63S3 Korlen
32–63A PV DC MCB 2P 15kA KNB2-63S6Z Korlen
6–25A DC Miniature Circuit Breaker 2P 6kA KNB2-63S5Z Korlen
6–25A MCB Breaker 4P 4.5kA Type B/C/D KNB2-63S1 Korlen
DC Miniature Circuit Breaker 1P 6–25A 6kA KNB2-63S5Z Korlen
DC Miniature Circuit Breaker 1P 6–25A DC Rated KNB2-63S6Z Korlen
DC Miniature Circuit Breaker 2P 6–25A for Solar PV Strings KNB2-63S6Z Korlen
Molded Case Circuit BreakersMolded-case breakers for higher current circuitsAll Products
1000–1600A 3P MCCB 690 V AC KNM1 Korlen
250–400A DC MCCB 2P / 3P 500 V DC KNM7DC Korlen
630–800A DC Moulded Case Breaker 2P / 3P 1000 V DC KNM7DC Korlen
Compact Circuit Breaker 3P 2000A 690 V AC DIN Rail or Panel Mount KNM1 Korlen
Compact Circuit Breaker 4P 2000A for Main Distribution KNM1 Korlen
DC Compact Circuit Breaker 2 or 3 Pole 400–630A 500 V DC KNM7DC Korlen
DC Compact Circuit Breaker 2P / 3P 400–630A 1500 V DC, for PV and Storage KNM7DC Korlen
DC Compact Circuit Breaker 2P / 3P 400–630A for DC Distribution KNM7DC Korlen
Residual Current Circuit BreakersShock protection for AC installations.All Products
100–125A RCCB 4P Type A KNL5-125 Korlen
2P RCCB Circuit Breaker Type B 100–125A KNL5-100 Korlen
2P Residual Current Circuit Breaker Type A 63–100A KNL5-100 Korlen
63–100A Residual Current Circuit Breaker 2P Type B KNL5-100 Korlen
Double Pole Residual Current Breaker 100–125A Type A KNL5-125 Korlen
Four Pole RCCB 100–125A Type A KNL5-100 Korlen
RCCB 4P 100–125A, Type AC KNL5-100 Korlen
RCCB 4P Type B 100–125A KNL5-100 Korlen
RCBOsCombined overcurrent and residual current protectionAll Products
RCBO 1P+N 10–63A 10kA KNLN6-63 Korlen
RCBO Circuit Breaker 1P+N 10–63A for Final Circuits KNLN6-63 Korlen
Surge Protective DevicesSurge protection for AC boards and DC PV arrays.All Products
DC SPD Type 1+2 Imax 40kA 800 V DC 2P KNY2-40PV Korlen
DC SPD Type 1+2 Up 4.5 kV 2P 1500 V DC KNY2-40PV Korlen
DC Surge Protection Device Type 1+2 1000 V DC 2P Imax 40kA KNY2-40PV Korlen
DC Surge Protection Device Type 1+2 Imax 40kA 2P 600 V DC KNY2-40PV Korlen
Double Pole Surge Arrester Type 1+2 Imax 50kA KNY2-10 Korlen
Four Pole Overvoltage Protection Device Type 2 Imax 10kA KNY2-10 Korlen
Overvoltage Protection Device Type 1+2 2P Up 1.5 kV KNY2-40 Korlen
Overvoltage Protection Device Type 1+2 In 20kA 4P KNY2-10 Korlen
FusesFuse holders used on PV string protection.All Products
DC Fuse with Holder 1000 V DC 2–32A 10×38mm KNRT-32M Korlen
gPV Fuse and Base 1500 V DC 1–35A KNRT-35DC Korlen
Isolating SwitchesLoad-break and isolating switchesAll Products
32A DC Load Break Switch 300 V DC DS1-32 Doxu
32A PV Isolating Switch 1000 V DC 2P DS1-32 Doxu
32A Solar DC Disconnect Switch 1200 V DC DS1-32EL/2-MC4-H Doxu
DC Isolator Switch 1200 V DC 16–32A DS1-32EL/4P Doxu
DC Isolator Switch 300 V DC 32A 2P DS1-32 Doxu
DC Isolator Switch 4P 32A 1000 V DC DS1-32 Doxu
DC Isolator Switch 600 V DC 32A DS1-32 Doxu
DC Load Break Switch 1200 V DC 2P 32A DS1-32 Doxu
Contactors & Motor StartersContactors, thermal relays and startersAll Products
AC Contactor 3P 9–95A 660 V AC KNC1 Korlen
Building Automation Contactor 16–25A 3P 400 V AC KNHC Korlen
Building Automation Contactor 1P 32–63A for Building Services KNHC Korlen
DIN Rail Contactor 1P 80–125A up to 400 V AC KNHC Korlen
DIN Rail Contactor 3P 32–63A 400 V AC KNHC Korlen
Double Pole Modular Contactor Relay 32–63A up to 400 V AC KNHC Korlen
Four Pole Building Automation Contactor 80–125A up to 400 V AC KNHC Korlen
Manual Motor Starter 3P 1–80A 690 V AC KNS12 Korlen
Combiner & Distribution BoxesEnclosures for string combining and AC distribution.All Products
DC Combiner Box 2 in / 2 out 1000 V DC for PV Plants KNX5PV-H/B-2/2 Korlen
Distribution Board 6–36 modules Watertight Enclosure KNS Korlen
Distribution Board IP65 4–24 modules KNHA Korlen
PV Combiner Box 1000 V DC 1 in / 1 out KNX5PV-H/B-1/1 Korlen
PV Combiner Box 1000 V DC 4 in / 2 out KNX5PV-H/B-4/2 Korlen
PV String Combiner Box 2 in / 1 out 1000 V DC KNX5PV-H/B-2/1 Korlen
PV String Combiner Box 6 in / 2 out 1000 V DC, KNX5PV-H/B-6/2 Korlen
Solar String Combiner Box 3 in / 1 out 1000 V DC KNX5PV-H/B-3/1 Korlen
Cable GlandsCable entry glands for enclosures and panelsAll Products
Cable Gland IP68 PA66 nylon PG7-PG63 WZCHDA
Nylon Cable Gland IP68 PG7-PG63 PG thread WZCHDA
PA66 Cable Gland metric M thread M8-M114 IP68 WZCHDA
Waterproof Cable Gland IP68 metric M thread WZCHDA
Cable TiesCable ties for bundling and fixingAll Products
Cable Tie Nylon 66 1.9-10 mm 60-1500 mm ZHEJIN
Heavy Duty Cable Tie SS304 / SS316 stainless steel 4.6-12 mm ZHEJIN
Metal Cable Tie PVC Coated SS304 / SS316 4.6-12 mm ZJS-PC ZHEJIN
SS Cable Tie 12.3 / 16 / 25 mm ZJDS Double Head Heavy Duty ZHEJIN
Stainless Steel Cable Tie in SS304 / SS316 ZJS-BC ZHEJIN
Corrugated PipeCorrugated conduit for cable routingAll Products
PA66 Corrugated Conduit AD10-AD54.5 nylon Black WZCHDA
PE Corrugated Conduit polyethylene AD7-AD54.5 WZCHDA
