Muller operating hours counterr panel mount 7 digit muller bw3018 the muller bw3018 is a reliable 230v ac operating hours counter that records operating times in electrical systems machines heaters etc the counter is easy to install using the integral locking spring and the finger safe connections in line with vbg4 mounting in the panel requires an aperture of 50 x 28mm the large white digits and red decimals are clear and easy to read muller bw3018 operating hours counter panel moun