Watlow PPC-2000 - Manual (Page 65)

PPC-2000 User’s Guide Chapter 2: Hardware Installation
Doc.# 30002-00 Rev 2.3 Watlow Anafaze 41
Figure 2.21 Wiring Digital Inputs
Connecting Counter or Frequency Inputs
PPC-2010 module accepts a single-phase pulse signal from
devices such as encoders. Counts and frequencies of the inputs
may be scaled with user selectable parameters. See Setting up
User Selectable Linear Inputs on page 98 for more information.
The PPC-2010 module can accommodate encoder signals up to
24Vdc. The following figures illustrate connecting encoders:
Figure 2.22 Encoder with 5Vdc TTL Signal
Connecting Digital Outputs
The digital outputs sink current from a load connected to the
controller’s power supply, or another power supply referenced
to the PPC-2000 power common. Do not exceed +24 volts on the
outputs.
If you must tie the external load to ground, or if you cannot
connect it as shown in Figure 2.23 through Figure 2.25, use a
solid state relay to drive your load.
The outputs conduct current when they are LOW or ON. The
maximum current sink capability is 100mA at 24Vdc. They
cannot ‘source’ current to a load.
Digital
Input
Device
TB50
Digital In
Com
Frequency/Counter Input
Com
Encoder
+5Vdc
10 kOhm
TB50
PPC-2010
{Add examples with transistor inputs on
digital and pulse inputs.}