Siemens SIMATIC S7-1500 Manual page 21

Supply voltage L+/M
Connect the supply voltage (24 V DC) to the L+ and M connections. An internal protective
circuit protects the technology module from polarity reversal of the supply voltage. The
technology module monitors the connection of the supply voltage.
ThePWR LED (Page 44) at terminal 19 indicates the presence of supply voltage.
RS422/TTL and 24 V pulse output signals
The technology module can output pulse signals either via the RS422/TTL or 24 V signal
interface for each channel. The pulse signals are designated with P/A and D/B.
A TTL pulse signal and a 24 V pulse signal use a single wire. An RS422 pulse signal uses a
pair of wires and the pulse information is transmitted as differential voltage. This ensures
interference-free transmission of RS422 encoder signals, even of higher-frequency signals
over longer distances. The RS422 wire pairs must be twisted in the cable and terminated
with a 100 Ω resistance.
For an overview of the signal types you can output, see section Pulse Train Output (PTO)
(Page 14).
When the RS422/TTL signal interface is used, you connect the P/A signal to the Chn.P/A
connections and the D/B signal to the CHn.D/B connections. When the 24 V signal interface
is used, you connect the P/A signal to digital output DQn.0 and the D/B signal to digital
output DQn.1. When the 5 V TTL signal interface is used, you must provide a resistance of
220 Ω to 1 kΩ between connection CHn.P/A and ground M as well as between connection
CHn.D/B and ground M.
The outputs of the channels are not electrically isolated from each other. The outputs are
electrically isolated from the backplane bus.
Digital inputs DI0, DI1 and DIQ2
Up to three digital inputs are available per channel. The digital inputs are used for additional
functions for the respective drive control:
Function
Reference switch input
Measuring input
"Drive ready" input
The digital inputs of the channels are not electrically isolated from each other. The digital
inputs are electrically isolated from the backplane bus.
Technology Module TM PTO 4 (6ES7553-1AA00-0AB0)
Manual, 12/2016, A5E38896703-AA
Meaning
You can use a reference switch at digital input DIn.0 to synchronize the
reference mark with the current position of the drive axis.
You can use a measuring input at digital input DIn.1 to save the current
position of the drive axis.
You can use digital input DIn.0, DIn.1 or DIQn.2 as an input for the ready
signal of the drive.
Connecting
3.1 Pin assignment
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