My OCXO (C-Mac, LVCMOS, 3.3V supply) draws 700mA for 5 minutes or so, then it drops to ~350mA (at room temperature).
My plan was to use an electronic load to increase the current draw on the 5V line slowly towards 800mA or so and check if the voltage drops.
I'm just too lazy to set up this test today. Chances are this will only happen when I have some more time at the weekend.
Anyway, the bridge rectifier CR28 is quite a beefy part even though it's unclear if it's the 5A (parts list) KBL-005 or the 8A (schematic) version KBU8A.
There are no markings visible on the accessible side but from the looks of it, I would tend to say it must be a KBU type (hole in it), so probably the schematics are correct.
When I'm at it, I will also check the voltages and the 10MHz signal on pin 10 of J4.
[Edit]
What I quickly tested today is the power consumption. It's about 23W in idle ("0" displayed) and ~24W if all LED digits are used. Assuming an optimistic 90% efficiency of the transformer, this would mean like 21.6W on the DC side.
There's a 12V tap, but the +/-12V supply is limited to some opamps and the 5ppm oscillator, so I would assume that the 12V part is probably taking less than 1W ... maybe 0.5W or so. For the sake of convenience, let's say 21W are caused by the +/-5V supply. So by rule of thumb, there could be like ~4A drawn on the +/-5V rail. This is a bit more than I expected and probably I made a mistake somewhere and/or the transformer efficiency is more like 85% or so.
Still, there probably is a margin for the OCXO, especially if the bridge rectifier is actually the 8A type. If it's the 5A type, the first few minutes would be pushing it a little bit.