AS350B3 False NR Overspeed Indications
NR overspeed is a known issue on EC120 VEMD.
EC issued Information notice No 2010-I-63 dated 30-Oct-2008 related to NR overspeed on EC120B. They recomend replacing one resistor module located just behind Nr/Nf indicator.
I had NR overspeed on EC120B indicated on VEMD after flight without any sign or conditions related to overspeed (VEMD said NR overspeed for 0 seconds, no other overlimits). We replaced the resistor and no problems with NR overspeed since then.
See "EC120" topic on this forum - page 25, post No.495 and later - there are some VEMD problems mentioned there.
Regards