Usually indicates an input sensor error (broken wire or incorrect polarity).
The Yamatake SDC20 Go to product viewer dialog for this item.
(example URL pattern) https://www.azbil.com/xx/products/sdc20_manual.pdf (exact link changes; better to search)
Usually indicates an input error, such as a broken sensor or a wiring issue.
If your display starts blinking or showing codes, don't panic. Here are the most common alerts:
Yamatake SDC20 User Manual: A Comprehensive Guide to Setup and Operation