3
Output Waveforms
State Width Error (
∆S):
The
deviation, in electrical degrees, of
each state width from its ideal
value of 90°e.
Phase (φ):
The number of
electrical degrees between the
center of the high state of channel
A and the center of the high state
of channel B. This value is
nominally 90°e for quadrature
output.
Phase Error (∆φ):
The deviation
of the phase from its ideal value
of 90°e.
Direction of Rotation:
When the
codewheel rotates in the direction
of the arrow on top of the
module, channel A will lead
channel B. If the codewheel
rotates in the opposite direction,
channel B will lead channel A.
Optical Radius (R
OP
):
The
distance from the codewheel's
center of rotation to the optical
center (O.C.) of the encoder
module.
Index Pulse Width (P
O
):
The
number of electrical degrees that
an index is high during one full
shaft rotation. This value is
nominally 90°e or 1/4 cycle.
Definitions
Count (N):
The number of bar
and window pairs or counts per
revolution (CPR) of the
codewheel.
One Cycle (C):
360 electrical
degrees (°e), 1 bar and window
pair.
One Shaft Rotation:
360
mechanical degrees, N cycles.
Position Error (
∆Θ):
The
normalized angular difference
between the actual shaft position
and the position indicated by the
encoder cycle count.
Cycle Error (
∆C):
An indication
of cycle uniformity. The differ-
ence between an observed shaft
angle which gives rise to one
electrical cycle, and the nominal
angular increment of 1/N of a
revolution.
Pulse Width (P):
The number of
electrical degrees that an output
is high during 1 cycle. This value
is nominally 180°e or 1/2 cycle.
Pulse Width Error (
∆
P):
The
deviation, in electrical degrees, of
the pulse width from its ideal
value of 180°e.
State Width (S):
The number of
electrical degrees between a
transition in the output of channel
A and the neighboring transition
in the output of channel B. There
are 4 states per cycle, each
nominally 90°e.
Absolute Maximum Ratings
Storage Temperature, T
S .............................................................
-40°C to +100°C
Operating Temperature, T
A ........................................................
-40°C to +100°C
Supply Voltage, V
CC ...............................................................................
-0.5 V to 7 V
Output Voltage, V
O .................................................................................
-0.5 V to V
CC
Output Current per Channel, I
OUT ............................................
-1.0 mA to 5 mA
Shaft Axial Play ................................................
±
0.25 mm (± 0.010 in.)
Shaft Eccentricity Plus Radial Play ..................... 0.1 mm (0.004 in.) TIR
Velocity ........................................................................... 30,000 RPM
[1]
Acceleration .............................................................250,000 rad/sec
2[1]
Note:
1. Absolute maximums for HEDS-5140/6140 codewheels only.
HP [ AGILENT(HEWLETT-PACKARD) ]
