Understanding contactor ratings

Question

I intend to use a 3 phase contactor (MNX25). [Datasheet link here]

I am facing some difficulty in understanding whether the ratings are for each contact or for the entire product overall. For ex - MNX25 model (model that I want to use) has the following specs:

AC-1 category (resistive basically) mentions 45 A. Is it 45 A per channel/contact or 45 A in total? 45 A in total seems too less because it amounts to 15 A per contact. A small relay can do 16 A comfortably. This is a big device. If I want to use this to power up a single phase resistive load, what should be the max current rating of the load (assuming other two contacts are left empty).

AC-2,3,4 categories (motor loads) mention 15 HP. They also mention 3 phase (on the left side parameter section). If I want to use it for a single-phase motor (only one contact will be used to switch LIVE, rest two contacts will be empty), what max HP can I put on this safely (consider 220 VAC)? Is it safe to assume this contactor can handle 5 HP (single phase) pump? I am guessing any motor more than 5 HP will be 3 phase anyways.

Can you please help me understand this better?

Answer 1

Is it 45 A per channel/contact or 45 A in total?

The rating applies to all contact currents so, 45 amps per phase.

what max HP can I put on this safely (consider 220 VAC)? Is it safe to assume this contactor can handle 5 HP (single phase) pump?

15 h.p. is the 3-phase rating so, it's 5 h.p. per phase.

I am guessing any motor more than 5 HP will be 3 phase anyways.

I would imagine that you can get greater than 5 h.p. single phase motors.