User`s guide

1.3.5 Dual Speed Blowers
As shown in Figure 1–4, the SW300 enclosure has eight rear-mounted blowers
that pull air from the front of the cabinet to the rear. Connectors on the
backplane provide the +12 V dc of power to operate the blowers. Logic signals
allow the status of the shelf blowers to be monitored by the EMU. All operational
blowers are turned up to high speed when the following conditions exist:
• If a high warning temperature condition is detected by the EMU
• If a blower is defective or removed
• If a blower’s speed falls below the set point
Figure 1–4 Dual Speed Blowers (Cabinet Removed for Clarity)
CXO-4269A-MC
BLOWER 5
BLOWER 6
BLOWER 7
BLOWER 8
BLOWER 1
BLOWER 2
BLOWER 3
BLOWER 4
Introduction to the SW300 Enclosure 1–9