CHER – Crash Hardened Event Recorder

  1. The CHER is the train’s “black box”. Its primary purpose is to acquire and store train operating data to facilitate accident investigations.
  2. All trains operating on FRA-regulated railroads must contain a CHER, which records operating status as specified in 49 CFR 229.135(b).
  3. The CHER records PTC parameters and other train system status values onto an internal hardened solid state memory module designed to withstand crash impact, heat from fire, and underwater pressure.
  4. The CHER acquires PTC system data from the OBC and SDU via the PTC Ethernet network.
  5. Up to 48 pre-defined discrete digital (on/off) status signals can be monitored and recorded, including cab activation status, direction of travel, propulsion & braking commands, headlight and ditchlight status, and several other values.
  6. An auxiliary CHER input board monitors speed pulses (obtained from the axle generators), pneumatic brake pressures (obtained from external pressure transducers), traction motor current (obtained from an external current transducer), and vehicle system voltage.
  7. A PC-based software app is required to monitor real time CHER input data, and to analyze recorded data. CHER data can be downloaded by plugging a USB flash drive into the CHER’s download port.
  8. The CHER cannot record hit songs.