Isgus PERFECT 2040 Operating Manual page 32

(5) Connect impulse lines for slave clock connection.
→ Only if recorder is equipped with option module slave clock function/DCF"
→ unipolar and bipolar impulses, 12 V - 60 V, 2 - 10 mA.
The Installation is now finished.
To program the time recorder see chapter 4 "Getting Started".
If the recorder is to be programmed at a later date, insert the front cover and close
the recorder.
3-12 Installation
This connection is not polarity sensitive.
Chapter 3