5
The time required to neutralize a static charge on an item in the air stream depends on fan speed. Setting a higher fan speed
reduces time required to neutralize a static charge.
When using the 3M
™
Overhead Ionizing Blower 991A unit in an electronics assembly area, the ionized air stream should
cover as much of the work area as possible. The constant flow of ionized air will help prevent items such as work surfaces,
tools, materials and components from developing a static charge. Charged items introduced into a work area will be
neutralized and will remain neutral while in the ionized air stream.
3.2
Performance
Discharge Times Performance
Discharge time in seconds under fan (18”) is typically under 5 seconds. *Tested using high speed at 21°C, 55% R.H. in
accordance to ESD STM 3.1-2006.
Troubleshooting
This information provides a quick troubleshooting reference for the 3M Overhead Ionizing Blower 991A. Should any of
these possible solutions not solve the problem, contact 3M.
Problem
Cause
Solution
Unit fails to operate
Power cord not connected
Plug in to specified voltage source
Unit fails to operate Replace line cord
Faulty ac ground
Replace line cord
Flashing fault light
Power incorrectly supplied to unit
Cycle power to the unit using the unit’s key switch
Flashing fault light
Power incorrectly supplied to unit
Ensure that properly grounded recepticle is used
Fault light on steady
Dirty or damaged emitter tips, incorrectly calibrated
Clean tips using integrated brush, replace as
necessary, recalibrate
Excessively long discharge times
Dirty or damaged emitter tips, incorrectly calibrated
Clean tips using integrated brush, replace as
necessary, recalibrate
Excessively long discharge times
Slow fan speed, or long working distance
Increase the fan speed , or move the unit closer to
the work surface
Unit fails to hold setpoint
Dirty or damaged emitter tips
Clean tips using integrated brush, replace as
necessary, recalibrate
Fan is slow
Fan speed is set slow
Adjust fan control clockwise
4.0 Maintenance
4.1
General Maintenance
The Overhead Ionizing Blower 991A has been designed with low maintenance in mind. The only regular maintenance
suggested is emitter point cleaning, ion balance checking and ion output checking. Emitter point cleaning takes only
seconds. The Overhead Ionizing Blower 991A contains a balancing circuit that is inherently self balancing. This circuit
compensates for dirt build-up on emitters, emitter point wear, line voltage fluctuations and variations in air velocity.
Scheduled checking of the ion output and balance should be considered to assure quality audit requirements.
m
CAUTION
ELECTRICAL SHOCK HAZARD! Do not insert objects through intake or outlet grille.
4.2
Emitter Cleaning
To clean the ion emitters, simply rotate the point cleaner knob located at center of each outlet clockwise to the stop
(approximately one turn) and release. The spring-loaded point cleaning brush will return to its parking spot. Recommended
frequency of cleaning is once a week.
4.3
Air Inlet & Outlet Cleaning
The air inlet grill on the top of the unit and the ionized air outlets should remain clean to prevent restriction of air flow. They
can be cleaned with a soft brush or vacuum. Clean the air inlet grill and ionized air outlets once every three months or more
often if needed.
