MX960: 2x 250V AC Low Power Modules enough?

Hey all,

We have a MX960 with 4x AC 250V Low Power Supplies. (3x1700W + 1 Redundancy)

Actual power allocated is 2695W. All power supplies share the load in zone0.

During maintenance window we need to shut the power of 2x power Supplies.

Are the 2x 1700W power supplies enough?

In my calculation the power budget is okay (3400W available, 2695W needed),

BUT Juniper documentation tells me different things

a) 3 power supplies for "non redundancy" and 4 power supplies for "3+1 redundancy"

b) another table shows me "minimum power supplies needed: 2

....I am confused!