PV Test Equipment
Filter By Challenge

New Module Technology

Learning & Resources
Emerging PV Technologies

New Module Technology

The rapid commercialisation of TOPCon, heterojunction (HJT), perovskite, and tandem cell technologies is changing the field testing landscape in ways that existing IEC standards and conventional instruments are not fully equipped to address. Higher open-circuit voltages, different temperature coefficients, and unique degradation signatures all require updated measurement approaches. This section tracks the testing implications of emerging module technologies and provides practical guidance for technicians and engineers working with next-generation products.

Equipment Options
Entec Solar
E-1500
Fastest IV curve tracer on the market — up to 200 curves per hour, 0–1500V / 35A, ±0.5% accuracy at Pmax. E-Sens wireless sensor with 2 km range, bifacial albedo support, barcode reader, PVET cloud integration.
Sonel
PVM-1530
Professional 1500V multifunction PV meter — IV curve tracing (IEC 62446-1 Cat. 2), Voc, Isc, Riso at four test voltages (RISO+ and RISO−), bypass and blocking diode test, continuity, and STC correction per IEC 60891 via IRM-1 sensor.
Field Testing Guide
Reading IV Curves: A Field Technician's Guide
What a healthy IV curve looks like, how six common fault types deform it, and when alternative test methods can identify the same issue faster — or catch what the IV curve misses.
Emazys
Z300 HE
1500V PV tester with inrush current protection for HE and bifacial modules. Riso 0–99 MΩ, Voc, Isc, Rs, ground fault location. Bluetooth cloud-connected.
Emazys
Z300 PVT
1500V PV tester for conventional and PERC modules. Riso 0–99 MΩ, Voc, Isc, Rs, ground fault location. Bluetooth cloud-connected.
Articles
Articles Coming Soon
Content for this topic is in development. Sign up on the home page to be notified when new resources are published.
Frequently Asked Questions

TOPCon and HJT modules have higher open-circuit voltages per cell and lower temperature coefficients — particularly for Voc. HJT modules are especially sensitive to temperature during IV curve tracing because their very low Voc temperature coefficient (approximately −0.25%/°C versus −0.30% for PERC) means small temperature measurement errors translate to proportionally larger STC correction errors. Both also produce higher operating currents, increasing inrush current concerns at connection.

Check both the voltage rating and the inrush current protection rating. Many legacy IV tracers are rated to 1000V DC and cannot be used on 1500V strings at all. For those rated to 1500V, confirm whether the instrument has enhanced inrush current protection — HJT and TOPCon strings produce higher surge currents at connection than PERC strings of equivalent power. Using an instrument without appropriate protection risks damage to both the meter and its leads.

The IEC 62446-1 Riso test voltage requirements are determined by system voltage, not module technology. A 1500V TOPCon string requires the same minimum Riso test voltage as a 1500V PERC string — 500V minimum per standard, with 1000V being common practice for better fault sensitivity. What changes is that TOPCon modules may exhibit slightly different insulation characteristics at elevated temperatures due to their tunnel oxide passivation layer — worth noting when interpreting borderline readings.

PERC modules typically experience 1–2% LID in the first hours of light exposure due to boron-oxygen complex formation in p-type silicon. TOPCon modules use n-type silicon, which is not subject to classical boron-oxygen LID. HJT modules also use n-type silicon and show minimal LID. Both technologies may still exhibit light and elevated temperature induced degradation (LeTID) under specific conditions, but the magnitude and timescale differ from PERC — commissioning baselines should be established after initial light soaking per manufacturer guidance.

Yes. IEC TS 60904-1-2 governs IV measurement of bifacial devices including TOPCon and HJT, defining bifaciality coefficients and measurement conditions. IEC 60891:2022 Method 4 is the current recommended STC correction procedure for bifacial modules. IEC 62446-1 covers commissioning test requirements applicable to all c-Si module types including these technologies. Always use Geff rather than front-side irradiance alone when correcting measurements on bifacial TOPCon or HJT strings.