Schneider Electric — Acti9 C60NA-DC 2P 20 A / 1,000 V DC switch disconnector (A9N61690)

Our arithmetic on the 20 A figure: a common sizing practice multiplies a string’s short-circuit current (Isc) by 1.25 to get the minimum continuous current rating. A module with Isc of 14 A gives 17.5 A, within 20 A; a high-current module with Isc around 18 A gives 22.5 A, which exceeds it. If your string runs near 1,000 V, check the module’s Isc against this switch — or choose a higher-rated model.

The 1,000 V / 20 A rating is for the full voltage; at lower string voltages it carries more (32 A at 800 V, 50 A at 700 V). Strings are normally sized close to the inverter’s maximum input voltage on cold mornings, so use the rating at your worst-case open-circuit voltage.

Electrical durability is stated as 300 cycles (mechanical: 20,000). That is plenty for an isolator operated occasionally for maintenance, and not a device to use as a daily on/off switch under load.

Operating temperature is −25 °C to +70 °C, and the datasheet does not state an IP rating — it is meant for mounting inside an enclosure. Air inside a closed box on a sun-baked Indian roof can approach the upper limit, so ventilation and shading of the box matter.

The datasheet gives a voltage-drop figure of 100 mV at 20 A (5.02 mΩ, 2 W), so each unit dissipates a small amount of heat; across many strings in one box that adds up.

Follow Schneider’s wiring diagram for terminals and polarity: the sheet’s ratings assume the intended connection, and it does not show the wiring scheme.