Cut Sheet

ELECTROMAGNETIC FLUORESCENT BALLASTS
Atlas Full Line Catalog 2014-2015
5-2
Ballast Sound
The slight hum present in fluorescent lighting installations
originates from the inherent magnetic action in the core and
coil assembly of the ballasts. This hum may be amplified by
the method of mounting the ballast in the fixture – the fixture
design – and, more often than not, this hum is amplified by
the resonant qualities of the ceiling, walls, floors and furniture.
In planning a lighting installation, careful consideration must
be given to the selection of the fluorescent lamp ballast, the
lighting fixture and room components. These precautions will
help to achieve the quietest installation possible.
The choice of fluorescent lamp ballast should be made on the
basis of selecting the one rated quietest for a specific location
or interior as some ballast have a more discernable hum due
to basic construction features and electrical ratings.
* These sound ratings are based on measurements of Average Ambient noise levels during con-
ditions of normal occupancy. Audible ballast hum may appear amplified during exceptionally
quiet periods and at times when area is unoccupied.
For Any Installation in:
Average Ambient
Noise Level
Of Interior
Sound
Level
Rating*
TV or Radio Station, Library,
Reception or Reading Room,
Church, School Study Hall
20-24
Decibels
A
Residence, Quiet Office,
Night School Classroom
25-30
Decibels
B
General Office Area,
Commercial Building, Storeroom
31-36
Decibels
C
Manufacturing Facility,
Retail Store,Noisy Office
37-42
Decibels
D
Sound Ratings
Radio Interference Filter
Radio interface is caused by the action of the arc at the lamp
electrodes which creates a series of radio waves. This energy may
interfere with radio reception by:
1. Direct radiation from the fluorescent lamp to the aerial circuit.
2. Line feedback from the lamp through the power line to the radio.
3. Direct radiation from the electrical supply line to the aerial circuit.
To correct the first cause, it is recommended the radio and aerial
circuit be separated at least 10 feet from the fluorescent lamp and
the radio provided with a positive ground.
The second and third causes can generally be corrected by the
addition of an external capacitor-reactor filter. It is also desirable
that the radio and fluorescent lamp fixture be provided a supply
voltage from separate branch circuits.
Input
Volts
Catalog
Number
Line
Current
(Amps)
120-277 RIF-1
4.25
max.
Certifications
✓ ✓
Wiring
Diagram
1184¾
Dimensions (inches)
2
7
/
32
1
5
/
8
4
3
/
8
Length Width Height Mounting
For bottom leads with studs, add suffix -BLS
SOUND RATED A
FILTER
BLACK
WHITE WHITE
RED
LINE
Diag. 118