Guides · TOSUNLUX
How to protect appliances from grid overvoltage and undervoltage?
Too high a voltage burns electronics; too low a voltage overheats the motors of refrigerators, air conditioners and pumps. A voltage protector cuts the supply before the damage, then restores it by itself. The TOSUNLUX (Tosun) range has models for the whole panel or for a single appliance.
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The short answer
- A whole single-phase home: TDP-1, at the head of the panel.
- Three-phase installation: TDP-3 (voltage) or TDP-2-3 (voltage and overcurrent).
- A single appliance (refrigerator, air conditioner, TV): a plug-in protector TS-VPDB2000 or TS-VP3000.
- Lightning is another matter: it calls for a surge protective device.
Overvoltage, undervoltage: what are we talking about?
The single-phase grid is designed for 220-230 V. A lasting overvoltage (broken neutral, imbalance between phases) can push the voltage far above that and destroy circuit boards and power supplies within seconds. Prolonged undervoltage makes motors draw more current, so they overheat and wear out. The sudden return of power after an outage is also a risky moment for compressors.
A voltage protector measures the voltage continuously, cuts off outside the thresholds, then waits for a delay before restoring power: appliances only restart once the voltage is back to normal.
TOSUNLUX models and their settings
| Model | Supply | Current | What it monitors | Settings (FAPELEC catalogue) |
|---|---|---|---|---|
| TDP-1 | 220 V single phase | 32 · 40 · 63 · 80 A | Overvoltage, undervoltage | Overvoltage 230–300 V, undervoltage 120–210 V, reclosing 10–600 s |
| TDP-3 | 380 V three phase (3P+N) | 32 · 40 · 63 · 80 A | Voltage of each phase | Same thresholds per phase, neutral required |
| TDP-2-1 · TDP-2-3 | 220 V single · 380 V three phase | 40 · 63 A · 63 · 80 A | Voltage and overcurrent | Overcurrent adjustable from 1 A to the rating, reclosing 1–600 s (TDP2-1) |
| TDP-4 | 220 V single · 380 V three phase | 32 to 80 A · 63 / 80 A | Voltage and overcurrent, motorised switching | Overcurrent 1 A to rating, delay 1–60 s, reclosing 10–999 s |
| TS-VPDB2000 | 230 V socket | ≈ 16 A | Voltage of one appliance | Adjustable thresholds and delay, display |
| TS-VP3000 | 230 V socket | ≈ 16 A | Voltage of one appliance | Fixed thresholds ≈ < 170 V and > 260 V, indicator lights, C-Start button |
How to choose the rating
The protector rating must cover the current of the installation it feeds, like the incoming breaker upstream. The catalogue also gives the maximum load: 6.6 kVA for the 32 A TDP-1, 8.8 kVA at 40 A, 13 kVA at 63 A and 17 kVA at 80 A; in three phase, from 20 kVA (TDP-3 32 A) to 52 kVA (80 A).
The TDP-1 is 52 mm wide on the rail, the TDP-3 90 mm: plan the space in the enclosure.
Voltage only, or voltage and current?
The TDP-1 and TDP-3 monitor voltage. The TDP-2 and TDP-4 also monitor current: they cut off on overcurrent too, with an adjustable threshold. This is useful for a pump, a workshop or a shop, where you want to detect an overload and display the current drawn. The TDP-4 switches with a motorised mechanism and recloses automatically once conditions are back to normal.
For a pumping station, see the guide protecting a pumping station.
And lightning?
A voltage protector reacts to lasting variations, in milliseconds. A lightning strike produces an overvoltage of a few microseconds that only a surge protective device can divert to earth, such as the type 2 TSP7-40. The two devices complement each other.
Frequently asked questions
Which voltage protector for a house in Morocco?
For single phase 220 V, the TDP-1 at the head of the panel, from 32 to 80 A depending on the incoming breaker. For three phase, the TDP-3.
What is the difference between a voltage protector and a surge protective device?
The voltage protector cuts off on lasting grid overvoltage and undervoltage. The surge protective device diverts the very short surges caused by lightning. They complement each other.
Can a single appliance be protected?
Yes, with a TS-VPDB2000 plug-in protector (display, adjustable thresholds) or a TS-VP3000 (indicator lights), plugged between the socket and the appliance.
Does the TDP-1 restore power by itself?
Yes. After a cut-off it waits for an adjustable delay of 10 to 600 s, then recloses once the voltage is back within the thresholds.
TOSUNLUX series mentioned
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