Published July 31, 2026 — PES Supply Brand Guide
Hoymiles: Microinverter Specialist Brand Guide
Hoymiles Power Electronics has established itself as the cost-effective alternative to Enphase in the microinverter market. While Enphase dominates the premium segment, Hoymiles delivers module-level power electronics at significantly lower cost per watt, making microinverter economics viable for a broader range of installations. The company's HM, HMS, and HMT series cover single-module, dual-module, and quad-module configurations, and the 2026 launch of the HiFlow Pro—the first US UL 3700-compliant plug-in microinverter—positions Hoymiles at the forefront of the emerging plug-in solar market. For PES Supply customers choosing among 50,000+ SKUs from 169 authorized brands, Hoymiles represents the value-driven microinverter option for installers who want module-level optimization without Enphase pricing.
Browse our complete selection of Hoymiles microinverters. Pair them with solar panels and racking and mounting for a complete system. Standard delivery is 7-10 business days.
1. Company Overview
Hoymiles Power Electronics Inc. was founded in 2011 and is headquartered in Hangzhou, Zhejiang Province, China. The company specializes exclusively in module-level power electronics (MLPE)—microinverters and related monitoring hardware—rather than attempting to compete across the full inverter spectrum. This focused strategy has allowed Hoymiles to optimize its products for cost efficiency and reliability in the microinverter form factor. Hoymiles has shipped millions of microinverters globally and maintains international offices including European support operations. The company is publicly listed and has grown to become the second-largest microinverter manufacturer by volume, behind Enphase.
Hoymiles's market position is defined by value and accessibility. The company's microinverters deliver module-level MPPT tracking, monitoring, and rapid shutdown at price points 30-40% below comparable Enphase products. While Hoymiles does not match Enphase's 25-year standard warranty across all product lines (the HM series carries 25 years, but HMS/HMT series carry 12 years standard, extendable to 25), the cost savings often outweigh the warranty difference for budget-conscious installations. The 2026 launch of the HiFlow Pro, certified to the new UL 3700 standard for plug-in solar, opens an entirely new market segment that Hoymiles is first to address in the United States.
2. Current Product Lines
HM Series (1-in-1 and 2-in-1)
The HM series is Hoymiles's original microinverter line, featuring galvanic isolation via high-frequency transformer and dedicated MPPT per module:
- HM-300NT (1-in-1): 300VA output, single-module, supports panels 240W-405W+, 96.7% CEC peak efficiency, 25-year warranty
- HM-600NT (2-in-1): 600VA output, dual-module, 25-year warranty
- HM-800NT, HM-1000NT, HM-1200NT: Higher-power variants supporting larger modules
The HM series is designed for the North American market with 240VAC output, NEMA 6 (IP67) enclosure, and compliance with NEC 2017/2020 rapid shutdown, IEEE 1547, UL 1741, and CA Rule 21.
HMS Series (4-in-1, Single-Phase)
The HMS series is Hoymiles's newer single-phase microinverter platform, supporting higher-power modules and featuring Sub-1G wireless communication:
- HMS-1600-4T: 1600VA output, 4-in-1 design (four modules), 96.7% CEC peak efficiency, 99.8% MPPT efficiency, 12-year warranty
- HMS-2000-4T: 2000VA output, 4-in-1, supports modules up to 670W, Sub-1G wireless
- HMS-800-2T: 800VA, 2-in-1 variant for smaller installations
The HMS series features 4 independent MPPT trackers (one per module), Sub-1G radio communication for stable long-range data transmission, and fanless IP67 convection cooling.
HMT Series (4-in-1, Three-Phase)
The HMT series extends Hoymiles microinverters to three-phase applications, better suited for commercial and industrial installations:
- HMT-2000-4T: 2000VA three-phase output, 4-in-1 design, 16A max DC input current, 12-year warranty (extendable to 25)
- Compatible with 182mm and 210mm high-power PV modules
- Integrated grid protection relay
HiFlow Pro (Plug-In Microinverter, 2026)
Launched in July 2026, the HiFlow Pro is the first microinverter in the United States certified to UL 3700, the new safety standard for plug-in (balcony) solar applications:
- 360W rated output per unit, with up to 4 units in parallel for 1,200W total
- 99.8% static MPPT efficiency, 99.5% dynamic MPPT efficiency
- NEMA Type 6 enclosure, operates -40C to +65C
- Plug-and-play setup in under 60 seconds via Bluetooth and Wi-Fi
- Anti-islanding and pin de-energization within 1 second of disconnection
- 250,000 hours of reliability testing
Eight states currently have legislation authorizing plug-in solar: Colorado, Connecticut, Maryland, Maine, New Hampshire, Utah, Vermont, and Virginia, with over two dozen more considering legislation.
3. Recent Releases (2025-2026)
The headline release of 2026 is the HiFlow Pro, launched in July 2026 as the first US microinverter certified to UL 3700 for plug-in balcony solar. This product opens the plug-in solar market that was previously unaddressed by certified hardware in the United States. Hoymiles also expanded the HMS and HMT series with higher-power variants supporting modules up to 670W, addressing the trend toward larger-format panels. The S-Miles Cloud monitoring platform received updates including improved fleet management features and the S-Miles Installer app for commissioning and diagnostics. Hoymiles also introduced the HIT series hybrid inverters (HIT-5L-G3 to HIT-20L-G3, three-phase, 5-20kW) with integrated EMS, 4 MPPT, and parallel stacking up to 10 units, expanding the company's product range beyond pure microinverters into the hybrid space.
4. Certifications & Listings
- UL 1741: HM and HMS series certified for US grid interconnection
- UL 3700: HiFlow Pro is the first US microinverter certified to this new plug-in solar safety standard (2026)
- IEEE 1547: Compliance with interconnection standards for distributed energy resources
- California Rule 21: Smart inverter certified for California interconnection (HM series)
- NEC 2017/2020 Rapid Shutdown: Module-level voltage reduction compliant with NEC 690.12
- NEMA 6 (IP67): Enclosure rated for outdoor installation in dust and heavy water-jet environments
- EN 50549-1 / VDE-AR-N 4105: European grid compliance for international market
5. Warranty Terms
Hoymiles offers a tiered warranty structure by product line:
- HM series: 25-year standard warranty—matching Enphase and the longest in the microinverter category
- HMS series: 12-year standard warranty, extendable to 25 years through paid extended warranty
- HMT series: 12-year standard warranty, extendable to 25 years
- HiFlow Pro: Warranty terms to be confirmed; product backed by 250,000 hours of reliability testing
The HM series 25-year warranty is a significant competitive advantage, as it matches Enphase's warranty at a lower price point. For HMS and HMT series, the 12-year base is shorter than Enphase's 25 years, but the cost savings typically justify the difference for budget-conscious installations. Warranty registration via S-Miles Cloud is required.
6. Popular Products at PES Supply
| Model | Type | Power | MPPT | Efficiency | Key Features | Price Range |
|---|---|---|---|---|---|---|
| Hoymiles HM-300NT | 1-in-1 microinverter | 300VA | 1 | 96.7% CEC | Single module, 25-yr warranty, NEMA 6 | $110-$140 |
| Hoymiles HM-600NT | 2-in-1 microinverter | 600VA | 2 | 96.7% CEC | Dual module, 25-yr warranty | $180-$230 |
| Hoymiles HMS-1600-4T | 4-in-1 microinverter | 1600VA | 4 | 96.7% CEC | Quad module, Sub-1G, 12-yr warranty | $280-$350 |
| Hoymiles HMS-2000-4T | 4-in-1 microinverter | 2000VA | 4 | 96.7% CEC | High-power, up to 670W modules | $320-$400 |
| Hoymiles HiFlow Pro | Plug-in microinverter | 360W | 1 | 99.8% MPPT | UL 3700, plug-and-play, 120V outlet | $180-$250 |
7. Technical Comparison
| Feature | Hoymiles | Enphase | APsystems |
|---|---|---|---|
| 1-in-1 warranty | 25 years (HM) | 25 years | 25 years |
| 4-in-1 warranty | 12 years (HMS) | 25 years (IQ8) | 25 years |
| CEC peak efficiency | 96.7% | 97% | 97% |
| MPPT efficiency | 99.8% | 99.4% | 99.5% |
| 4-in-1 option | Yes (HMS/HMT) | No (1-in-1 only) | Yes |
| Three-phase microinverter | Yes (HMT) | No | Yes |
| Plug-in (UL 3700) | Yes (HiFlow Pro) | No | Yes (EZ1) |
| Cost per watt | $0.15-$0.25 | $0.30-$0.45 | $0.20-$0.35 |
Hoymiles's competitive advantage is cost and configuration flexibility. The 4-in-1 HMS and HMT designs reduce per-module hardware and installation costs by handling four panels per unit, which Enphase does not offer (Enphase is 1-in-1 only). The three-phase HMT series opens commercial microinverter applications that Enphase cannot address. The HiFlow Pro gives Hoymiles first-mover advantage in the US plug-in solar market. The trade-off versus Enphase is the shorter 12-year base warranty on HMS/HMT series and a less mature software ecosystem. The HM series matches Enphase's 25-year warranty at a lower price, making it the strongest direct competitor.
8. Monitoring & Software
Hoymiles's monitoring is delivered through the S-Miles Cloud platform, accessed via the DTU communication gateway:
- S-Miles Cloud: Cloud-based monitoring with module-level production data, fault alerts, and system performance analytics
- S-Miles Installer app: Mobile app for installers providing commissioning, account configuration, visual physical layout guides, and module-level diagnostics
- DTU gateway: Data Transfer Unit that collects data from microinverters via Sub-1G wireless and transmits to S-Miles Cloud via Wi-Fi. Multiple DTU variants (DTU-Pro, DTU-WLite-S) support different system sizes and communication ranges up to 400m open space
- Module-level monitoring: Per-panel production visibility with alarm and fault detection at the individual module level
- Remote O&M: Remote diagnostics, firmware updates, and maintenance management for distributed PV plants
- Local access: DTU supports Modbus (RS485/RTU or TCP) for local data access, though official local-mode documentation is limited; community DIY integrations exist for platforms like Home Assistant
9. Installation Notes
- Trunk cable architecture: Hoymiles microinverters connect to a trunk (bus) cable that carries AC power from all microinverters to the interconnection point. Use Hoymiles-compatible trunk cable and AC connectors. For single microinverter installations, use the appropriate entrainment connector; for multiple units, use intermediate and final connection kits.
- Module compatibility: Verify the microinverter's maximum input voltage (typically 60-65V) and input current (up to 16A per channel on HMS/HMT) match the panel specifications. HMS and HMT series support modules up to 670W. The HM series supports 240W-405W+ panels.
- Grounding: Hoymiles microinverters feature galvanic isolation via high-frequency transformer (HM series) and do not require separate DC grounding. Module frames are grounded through racking per NEC 690.43. HMS series may be transformerless in some configurations; verify grounding requirements per the installation manual.
- Rapid shutdown: Module-level rapid shutdown is built into the microinverters. When AC power is removed, each microinverter ceases output and the DC voltage at the panel drops to safe levels within NEC 690.12 time requirements. No separate rapid shutdown initiator is required for the module-level portion, though the AC disconnect must comply with NEC.
- DTU installation: Install the DTU gateway within Sub-1G wireless range of all microinverters (up to 400m open space). The DTU connects to the internet via Wi-Fi. Ensure the DTU is registered to an S-Miles Cloud installer account for monitoring activation.
- Grid code setup: Microinverters are pre-configured for standard grid parameters. For specific utility requirements or Rule 21 compliance, verify settings through the S-Miles Cloud platform. Commissioning is completed through the S-Miles Installer app.
- Parallel operation: Multiple Hoymiles microinverters on the same AC branch operate in parallel. Verify the total branch circuit current does not exceed the trunk cable and breaker ratings. The HiFlow Pro supports up to 4 units in parallel on a single branch circuit for 1,200W total.
10. FAQ
How does Hoymiles compare to Enphase?
Hoymiles offers similar module-level optimization and monitoring at 30-40% lower cost. The HM series matches Enphase's 25-year warranty. The HMS/HMT 4-in-1 designs reduce installation costs. The trade-off is shorter 12-year base warranty on HMS/HMT and a less mature software ecosystem.
What is the advantage of 4-in-1 microinverters?
A 4-in-1 microinverter handles four panels per unit, reducing hardware cost per panel and installation time. Each panel still gets independent MPPT tracking and monitoring. This makes microinverter economics viable for larger residential and commercial arrays.
What is the HiFlow Pro and UL 3700?
The HiFlow Pro is the first US microinverter certified to UL 3700, the new safety standard for plug-in (balcony) solar. It plugs directly into a standard 120V outlet, enabling renters and homeowners to generate solar without permanent installation. Up to 4 units can combine for 1,200W total.
Do I need the DTU gateway for monitoring?
Yes. The DTU (Data Transfer Unit) is required for S-Miles Cloud monitoring. It collects data from microinverters via Sub-1G wireless and transmits to the cloud via Wi-Fi. Without a DTU, the microinverters operate but cannot be monitored remotely.
How long does delivery take?
All Hoymiles orders from PES Supply ship within 7-10 business days. We do not offer same-day or free shipping.
Shop Hoymiles
Explore our full inventory of Hoymiles microinverters and DTU gateways. PES Supply carries 50,000+ SKUs from 169 authorized brands—your B2B electrical and solar distribution partner. Shop all Hoymiles products. Delivery is 7-10 business days on all orders.