I am not a customer of these fans yet, but expect to be shortly. This situation is fairly uniform for all the OEMs I browsed. The engineers select a motor hp that is a little higher than the manufacturer recommended for obvious reasons: OEM is putting his best foot forward, motors come in...
I have been thinking of the same subject (BT or DT), but as it applies to condensing units. The advantage BT has is that the motor is in the cooler upstream air, which will enhance it's life.
ChrisConley:
thanks for the response. The 1.437 BHP is off of actual fan performance curves. It corresponds to 11,200 cfm at 0.125"wc static pressure. The design engineer then has to allow for motor efficiency and pick a suitable motor that will have at least 1.437/0.8 = 1.79 HP power. The...
quark: Thanks very much. I am looking into fluid coolers (often called dry coolers) with direct drive motors, which mostly have cont. duty motors and steady air resistance. The 1.437 BHP is from the standard (common) cfm vs sp & cfm vs BHP fan performance curves. I will think out your...
Gentlemen:
Reference: thread403-82316
I seem to lose out on this subject. Please note the following:
Fan BHP = (cfm x static press “w.c.) / (6356 x fan efficiency)
Fam Motor HP = fan bhp / motor efficiency
Following are values from a propeller fan manufacturer's catalog for a particular fan...
