TFW Power Supply Fan Replacement ---------------------------------- Original Version 23-DEC-2010 Most Recent Version 10-JAN-2011 This note is about replacing the fans in the ASTEC VS Spectrum series power supplies. Each TFW power supply chassis holds 2 of the ASTEC VS Spectrum supplies. One of these supplies (the left one looking from the back) makes the +3.3 Volt power and the other one makes the +5V, -2V, and -4.5V power. Each ASTEC VS Spectrum supply has 3 internal fans. There is one large 119mm fan and two small 60mm fans. The original large fan is a Nidec Beta V model TA 450 DC B31257 16A. The original small fans are NMB model 2410ML 05W B50. The original large fan is being replaced with an EBM-Papst model 4214H. The comparison of the original and replacement large fans is shown in the following: Original Replacement Specification Nidec Bata V EBM-Papst 4214H ------------- ------------ --------------- nominal Voltage 24 V 24 V nominal Current 0.28 A 0.22 A bearing type ball ball Fan Speed rpm 3,250 - L10 Life Hrs. 57,100 - cfm at 0.00" 112 108 cfm at 0.08" 90 92 cfm at 0.16" 54 50 cfm at 0.24" 15 35 cfm at 0.32" 0 18 inch for 0 cfm 0.29 0.39 EBM-Papst Part Num 4214H DK Part Num 381-1085-ND about $46 each The big Nidec Beta V fan when stalled draws about 0.80 Amps or a little more. The small NMB fan when stalled or at startup draws about 0.20 Amps. At least in the +3.3V supplies there is a large ceramic capacitor on the mother board that get folded over because it interferes with the 240 Amp module next to the power entry module. This capacitor is labeled: CM 225 M5E. This must be a 2.2 uFd ceramic capacitor. Some probable replacements from DK are: DK Num 399-4434-ND Kemet C340C225M5U5TA <-- This is Z5U DK Num 399-4433-ND Kemet C340C225K5R5TA <-- This is X7R To clear the 240 Amp module this "mother board" capacitor needs to be moved back in the direction of the power entry module and toward the air & power output end of the chassis and then RTVed on top of the other components there. Swap the "has been providing power for 10 years" and the "has been running but not used" +3.3V inverter modules in the +3.3V supplies. The original small fans are being replaced with an EBM-Papst model 624N. The comparison of the original and replacement small fans is shown in the following: Original NMB Replacement Specification 2410ML 05W B50 EBM-Papst 624N ------------- -------------- --------------- nominal Voltage 24 V 24 V nominal Current 0.10 A 0.09 A bearing type ball ball Fan Speed rpm 4,900 6,100 L10 Life Hrs. - 72,500 cfm at 0.00" 23 23 cfm at 0.08" 15 19 cfm at 0.12" 11 12 cfm at 0.16" 8 9 cfm at 0.20" 4 7 cfm at 0.24" 2 5 inch for 0 cfm 0.25 0.30 EBM-Papst Part Num 624N DK Part Num 381-2272-ND about $30 each - Recall that the inverter modules come out of the chassis by pulling "up" on them but the power entry module comes out of the chassis by pulling it off to the side. - Tighten DC power screw connections - Replace ceramic capacitor - Wash and clean with air hose - Routing, Insulation, Cable Ties, of DC fan wires - Insulate mounting screw from fan wires - Shorter or no mounting screw under the fan - Label the brick as to having new fans and their replacement date