1 to 24 Configurable Strings
The T-SMB-300 isn't a fixed-channel box. Input string count is configured to your array design, from a small commercial rooftop combining a handful of strings to a utility-scale block consolidating two dozen.
Smart PV DC Combiner & String Monitor
String Monitoring Box (SMB): T-SMB-300 PV Array DC Combiner and String Monitoring Solution
String Monitoring Box (SMB) functions as a photovoltaic DC junction box. It links 1 to 24 solar strings to a single parallel point. The unit records the current of each string, the system voltage, and the internal temperature. This system enables your team to pinpoint underperforming strings and fault causes within minutes. You need not wait for monthly inspections or a drop in total plant output to detect problems.
1 to 24 configurable input strings
Up to 1500 V DC, 630 A DC measurement
IP66-rated polycarbonate/FRP enclosure
RS-485, fibre optic or wireless output
Key Features
Engineered for Maximum String-Level Visibility
Every DC combiner protects an array. The T-SMB-300 is built to do more than that: it tells you, string by string, which parts of your array are earning their keep, so a shaded panel, a loose MC4 connector or a degraded module doesn't sit undetected for a full billing cycle.
1500 V DC Isolation, String by String
DC circuit breakers are rated at a minimum of 1500 V DC, and each input string carries its own DC fuse for individual overcurrent protection, so a fault on one string trips locally instead of taking the whole combiner offline.
Per-String Fault Detection
Input current is measured individually per string, at ±0.25% accuracy, alongside system voltage and internal temperature (0°C to 100°C range). That's the resolution needed to separate a genuinely faulty string from normal weather-driven variance.
Class 2 / T1+T2 Surge Protection
DC power SPD and Modbus SPD are both included, sized by MPPT count and rated across 600 V, 1000 V and 1500 V classes, protecting the combiner and the communication line behind it from transient surges.
Automated Remote Alarms
Bus voltage is monitored in real time. When a fault or a performance threshold is breached, the unit generates an alarm automatically and dispatches a notification to the designated maintenance team, cutting the gap between a fault occurring and a technician knowing about it.
Multi-Protocol Communication
Measured data cascades from the String Monitor to the next device on the bus over Ethernet, RS-485, fibre optic or wireless, all the way through to the solar inverter, so the SMB fits into whatever communication backbone the plant already runs.
Applications
Where the String Monitoring Box (T-SMB-300) Is Deployed
From megawatt-scale ground mounts to floating arrays, the String Monitoring Box (T-SMB-300) adapts to how and where your strings are installed. Cable entry is bottom-mounted by default and customizable for floating projects.
Utility-Scale Solar Farms
Rooftop & Commercial (C&I) Solar
Ground-Mount Distributed Generation
Floating Solar (Floatovoltaic) Plants
Solar Plus Battery Storage (BESS) Hybrid Sites
EPC & System Integration Projects
O&M and Asset Management Portfolios
Agrivoltaic & Land-Constrained Installations
Technical Specifications
Complete enclosure, electrical, monitoring and certification details for the T-SMB-300.
Enclosure & Protection
| Parameter | Specification |
|---|---|
| Material | Polycarbonate / FRP |
| Degree of Protection | IP 66 |
| UV Resistance | Yes, UV-stabilised enclosure material |
| Locking Arrangement | Latch mechanism with locking provision |
| Mounting Type | Wall mount / Structure mount |
| Cable Entry | Bottom entry (customizable for floating projects) |
| DC Power SPD | Yes |
| Modbus SPD | Yes |
| SPD Class | Class 2 SPD / Class T1+T2 SPD, 600 V / 1000 V / 1500 V |
FAQ
Frequently Asked Questions
Ready to Protect Every String in Your Array?
Talk to a Sertel engineer for a tailored string count, voltage class and communication protocol for the T-SMB-300.