(12 Feb 2017, 11:42 am)S813 FVK wrote 5275 has always had a tachograph fitted - in its batch, it was the vehicle fitted with a tachograph (like 6071 on the TENs, 5391 on the X66 etc)According to a comment on my photo of 5275 on a Facebook Group last week:
5275 has had a Tachograph since new but was uncalibrated for quite a while, it wasn't calibrated until sometime early last year.