2.1
Signal interface
This drive uses the industry standard open-collector, low-level - true, multiplexed
interface convention. The industry standard open-collector, 40mA TTL driver 7438
or equivalent, is used to transmit the I/O signals. The transmitted signals are
detected by the hysteresis input inverter, 7414 or equivalent. A 150½ pull-up resistor
between the signal line and +5V is necessary on the receiving circuit. The input of
each receiver is terminated by a 150½ resistor and a diode. When using two or
more drives on a daisy chain, remove all plug jumpers "TM" except for the last drive
on the daisy chain.
The input signal lines which are not multiplexed are MOTOR ON and IN USE. The
input lines have the following electrical specifications. See figure 2-2 for the
recommended circuits.
True
=
Logical zero = Vin = +0.0 to +0.4V
@
I
in = 40mA (max.)
False =
Logical zero = Vin = +2.5 to +5.25V
@
I
in = 250µA (open)
Input impedance = 150½
2.2
Input lines
There are twelve active low TTL input lines to the drive. Individual signal line
characteristics are described overleaf.
9
+5V
TM
Diode
150
W
Max. 10 feet
ribbon or
twisted pair
7414
or equivalent
7438
or equivalent
Figure 2-2. Interface signal driver/receiver
Leaflet No. 9419 26/4/97 6:09 pm Page 9
