Tongwei · Fronius
Tongwei TNC TWMNH-54HD510 + Fronius Primo 8.2-1: how many panels per string
From 3 to 21 Tongwei TNC TWMNH-54HD510 panels per string on an MPPT input of the Fronius Primo 8.2-1 inverter — in any climatic region of Ukraine. Below: the window for each region, the input currents and example plants laid out by the Solispec engine.
- Panels per string
- 3–21pcs
- Input V_max
- 1,000V
- MPPT window
- 80–800V
- Panel I_sc
- 15.95A
- MPPT input I_sc
- 36.0A
- Panel V_mp in heat
- 29.1V
Ground frame designer
A ground plant with Tongwei TNC TWMNH-54HD510
The builder opens with this panel and the Fronius Primo 8.2-1 inverter: Solispec lays out the strings itself.
- No sign-up
- Snow and wind check
- Drawings and estimate
String by climatic region
T_min per ДСТУ-Н Б В.1.1-27:2010, табл. 1; open-circuit voltage at T_min: K_U = 1 + α·(T_min − 25)/100 = 1.16 (α -0.24 %/K, T_min -42 °C; Annex B).
| Region | T_min | Panel U_oc at T_min, V | Min per string | Max per string | String U_oc at max, V (≤ 1,000) |
|---|---|---|---|---|---|
| Region I | -40 °C | 46.73 | 3 | 21 | 981.2 |
| Region II | -42 °C | 46.92 | 3 | 21 | 985.3 |
| Region IIIA | -38 °C | 46.53 | 3 | 21 | 977.2 |
| Region IIIB | -32 °C | 45.95 | 3 | 21 | 964.9 |
| Region IV | -20 °C | 44.79 | 3 | 22 | 985.3 |
| Region V | -27 °C | 45.46 | 3 | 21 | 954.8 |
The minimum per string keeps the string voltage in heat (panel V_mp 29.1 V) above the MPPT window (80 V).
Input currents
| Panel I_sc / MPPT input I_sc, A | 15.95 / 36.0 |
|---|---|
| Panel I_mp / MPPT input I_mp, A | 14.92 / 18.0 |
| Parallel strings per MPPT | 1 |
| MPPT inputs | 2 |
No cautions about the currents.
Example plants
The Solispec engine laid out the strings for plants of several sizes with this inverter at the lowest T_min; only those that pass the checks with every panel placed are shown.
| Plant | Panels | kW DC | Inverters | Strings | DC/AC |
|---|---|---|---|---|---|
| ≈ 5 kW | 10 | 5.10 | 1 | 10 pan. × 1 — inv. 1, MPPT 1 | 0.62 |
| ≈ 10 kW | 20 | 10.20 | 1 | 20 pan. × 1 — inv. 1, MPPT 1 | 1.24 |
| ≈ 15 kW | 30 | 15.30 | 2 | 15 pan. × 1 — inv. 1, MPPT 1; 15 pan. × 1 — inv. 2, MPPT 1 | 0.93 |
- DC/AC 0.62 — inverter oversized
- взимку Vmp 835 В > 800 В — вище MPPT
A preliminary calculation; a design needs an engineer's check. Solispec engine 0.12.0.