- 116 -
Figure 29
Cable Shielding
In addition to the described signals, the following voltage and ground signals are in the
connector.
Signal
Pin Number
1)
+5
(25, 26, 27, 28)
2)
+15
(34)
3)
GRD (Logic Common)
(29, 30, 31, 32)
4)
+BUS
(33)
5)
SHIELD
(37)
These signals are provided for the parallel interface options only and cannot be used for any
other purpose. The thumbwheel multiplexing uses +15, +BUS, GRD and SHIELD.
Thumbwheel Wiring
The 37-pin parallel interface connector and a typical thumbwheel wiring schematic are shown on
the following pages. All the necessary connections are shown. However, there are several
important considerations:
1.
The in15VDC logic supply of the drive should be used for the
thumbwheel supply voltage. This connection is made by connecting pins 33 and
34 on the 37-pin connector (P2).
2.
The cable used to connect the thumbwheel assembly to the 37-pin connector (P2)
must not exceed 50 ft. in length. Also, this cable must be shielded with one end
of the shield connected to pin 37 of P2. The other end of the shield must not be
connected. Typical wire gauges used in this cable would be from 26 AWG to 32
AWG.
3.
The thumbwheel digits must have the blocking diodes that are indicated on the
wiring schematic. If not, the diodes can be added according to the schematic. A
typical diode used for this would be a 1N914.
4.
The 1, 2, 4, 8 coding for the data must be accomplished with BCD switches that
are active “ON”. These are the most common variety.
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com
