Cooling Water; Exhaust; Control System; Warning - EBARA ESA300W Instruction Manual

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3.1.3 Cooling Water

Because the pump compresses gas from a vacuum to atmospheric pressure,
compression heat is generated. Therefore cool the motor and jacket at the bottom
of the casing with cooling water.
The cooling water connector takes the form of a coupler for easy connection and
disconnection.

3.1.4 Exhaust

A check valve is provided as a standard accessory to prevent reverse flow of gas
from the exhaust through the pump to the vacuum chamber when pump is
stopped.

3.2 Control System

This pump has a built-in measuring unit consisting of an Earth Leakage Breaker
(ELB), an Electro-magnetic switch and a control circuit.
To improve reliability and safety, a sensor monitors the condition of each utility
and pump section.
During pump operation all operating conditions are monitored, including power
supply, cooling water flow, N2 gas flow and motor coil temperature, motor speed,
and motor current.
Pump operation "rides through" a transient power outage up to 1 second long.
(Two-second ride through is available as an option.)

3.2.1 Warning

To assure the reliability of the pump as a vacuum exhaust system, the pump
protection system generates two levels of alarm: WARNING and ALARM.
A WARNING signal is generated when pump operation exceeds the normal range.
It therefore only draws attention that the normal operating values are not adhered
to but does not signify that danger is imminent. The pump will continue to operate
in this condition.
An ALARM signal output is generated and the pump will stop automatically when
the upper mechanical safety limit is reached during pump operation.
EBARA
CORPORATION