Ebara Dry Pumps And Semi S2-93A (S2-0200) - EBARA A70W Instruction Manual

(VI)
Appendix 3

EBARA Dry Pumps and SEMI S2-93A (S2-0200)

In many cases, strict compliance with all aspects of the SEMI health and safety guidelines is
not the most desirable or economical way to meet the customer's actual needs. ETI
technical staff can assist the user's equipment engineers and safety professionals in
selecting the best practices for a specific installation. An appropriate guideline is evaluation
of the intended installed configuration of the system, including the pump, process tool,
power distribution and facilities. Items in question include:
Circuit Breaker
As a general practice equipment manufactured in the U.S. employs thermal-magnetic circuit
breakers for overcurrent protection. SEMI S2 further requires that these circuit breakers
have a minimum of 10,000 AIC (amp interrupt capacity). Many EBARA pumps, following
the common Japanese practice, employ an earth leakage breaker. Connecting the pump to
an appropriately rated circuit breaker in a distribution panel creates a system that meets the
SEMI requirements.
Lockout – Tagout
A nearby distribution panel may also be an appropriate location for the lockout-tagout
bracket.
Exhaust Dilution Flow Sensor
For pumps requiring auxiliary nitrogen in the exhaust, ETI offers a hardware-only, normally
open flow switch. However, the standard configuration is a firmware-driven shutdown,
executing through the pump processor and preserving an explanation of the trip.
Cabinet Exhaust Flow
Most customers prefer to monitor the condition of exhaust systems at the facility level rather
than the pump level.
Liquid Leak Detector
Because cooling water leaks inside a pump enclosure are extremely rare, most users find
that a liquid leak detector in each pump represents an unnecessary expense. Moisture
sensors on the subfab floor can detect a leak either from within a pump or from the utility
piping.
EBARA Dry Pumps and Ergonomics
SEMI S8-95, Safety Guidelines for Ergonomic/Human Factors Engineering of Semiconductor
Manufacturing Equipment, which is referenced in SEMI S2, specifies height ranges for
location of equipment controls and emergency off (EMO) buttons. The minimum height
exceeds the overall height of some EBARA A Series dry pumps.
Because vacuum pumps run unattended for long periods of time, EBARA's technical staff
believes that relocating the infrequently used controls is unwarranted. Should your vacuum
pump application require frequent manual operation of the controls, you may contact your
sales representative or the nearest EBARA office for assistance in mounting the controls at a
convenient height.
EBARA Corporation