6
Electrical Interface
To insure reliable encoding
performance, the HEDS-9040 and
9140 three channel encoder
modules require 2.7 kΩ (± 10%)
pull-up resistors on output pins 2,
3, and 5 (Channels I, A and B) as
shown in Figure 1. These pull-up
resistors should be located as
close to the encoder module as
possible (within 4 feet). Each of
the three encoder module outputs
can drive a single TTL load in this
configuration.
Figure 1. Pull-up Resistors on HEDS-9X40 Encoder Module Outputs.
Mounting Considerations
Figure 2 shows a mounting
tolerance requirement for proper
operation of the HEDS-9040 and
HEDS-9140. The Aligning Recess
Centers must be located within a
tolerance circle of 0.005 in.
radius from the nominal locations.
This tolerance must be
maintained whether the module is
mounted with side A as the
mounting plane using aligning
pins (see Figure 5), or mounted
with Side B as the mounting plane
using an alignment tool (see
Figures 3 and 4).
Figure 2. HEDS-9X40 Mounting Tolerance.
HP [ HEWLETT-PACKARD ]
