Multi-function counter with following details. Feature 1. Red led display 2. Backup data for power fail 3. Multi-function intelligent meter, used as counter frequency meter, Speed meter etc. By pressing four key(32 type) 4. Main fold relay output fashion Model and parameter 1.Counting signal impedance more than 100kª+ Input level h more than 5v; l less than 2v Max. Input 50v Step descend edge 2.Contact content ac220v 3a; dc24v 5a (resistive load ) 3.Noise elimination ratio more than nmr 40db (50hz/60hz) ía10% 4.Over range indication digital flashing 5.Operation temperature 0-50ípc,