Ventilation Requirements; Thermal Protection; Overheating Detection; Fan Failure - HP 81110A Quick Start Manual

Ventilation Requirements

The instrument is fitted with three cooling fans. Make sure that there is
adequate clearance of 80 mm at the rear and 25 mm at the top and bot-
tom to ensure adequate air flow. If the air flow is restricted the internal
operating temperature will be higher, reducing the instrument's reliabil-
ity or causing the instrument's thermal-protection circuits to automati-
cally switch off the instrument.
NOTE:

Thermal Protection

Overheating Detection

The instrument monitors its internal temperature. If the temperature
exceeds approximately 80
instrument will switch on again if the temperature falls below approxi-
mately 77

Fan Failure

If a fan is broken or prevented from operating by a blockage the temper-
ature will increase. When the temperature exceeds approximately 80
the overheating detection switches off the instrument for safety reasons.
For reliability it is recommended to send instruments with broken or
defective fans immediately to HP Service for repair.
HP 81110/04A User's Guide Installation & Safety Requirements
Do not cover the ventilation holes.
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Installation & Safety Requirements
Ventilation Requirements
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