Hotel load is a deep subject. Very difficult to quantify. All periscope operation was hydraulic, so no worries there. The ventilators were hardly run at sea except during charging and briefly to ventilate the boat after surfacing, so no worries there. Battery heating is hard to quantify, because the automatic regulator only kicked on when the electrolyte dropped below 30°C. But heating drew about 20 A. Eto Battery charging initially was 30 A, which tapered down to 22 as the torpedo battery cells approached gassing voltage. Hard to quantify. U-boat heating can be considered a non-issue as the electric heaters typically weren’t used on war patrol to save battery. Then there is all the other ancillary equipment on the regulated and unregulated circuits. At one point, back of the envelope, I calculated a hotel load on a typical day of about 200 A. That is also high as it assumes careless all-day use of the ventilators. So maybe cut that in half.
I do really like the idea of equipment drawing current. We have data on pretty much every piece of electrical equipment, so this could be modeled.
|