Modern 3-phase EMUs are driven through a Driving Desk with a Driver Display Unit (DDU) showing live status of every subsystem — pantograph, VCB, brakes, compressors — rather than the array of physical gauges and switches on older stock. This chapter covers the real sequences a motorman follows: energising, moving, stopping, cab changing, negotiating a neutral section, and the Rescue Drive Mode fallback.
Energising Sequence
- In the DTC: turn Battery supply switch ON for 2–3 seconds; the DDU screen becomes ready within seconds.
- Insert the DCS key and turn ON; turn ICS to open fully (BIV key) — all pilot lamps glow briefly then extinguish with alarm/bell sound.
- Confirm cab occupancy icon shows blue on the DDU, then briefly turn PANTO UP switch — panto raises (shown blue on DDU) and, as soon as it touches the contact wire, OHE voltage appears on the display.
- Briefly turn the MC (VCB) switch ON and confirm VCB closes. MAC (Main Air Compressors) start automatically; press Start All MAC if all four are needed — they run until 7 kg/cm² is reached, after which only 3 continue per the normal schedule.
- Holding brake applies automatically once energised, and BC (brake cylinder) pressure shows 0.8 kg/cm² — normal at standstill.
Moving & Stopping the Train
- To move: ensure BP is 5 kg/cm² and MR is 6–7 kg/cm², release parking brake, set reverser forward, twist MCH (master controller handle) to horizontal and move gently to traction side — holding brake releases automatically as the train starts moving.
- Cruise control (constant-speed operation) engages once the train exceeds a minimum 10 kmph — the CCU then maintains speed by adjusting each unit's tractive effort automatically, and cancels itself if speed can't be held, if the switch is pressed again, or if the master controller position changes.
- To stop: bring throttle to 0, then move MCH to the braking side — dynamic (regenerative) braking has first priority, with EP brake supplementing only if the dynamic brake effort is insufficient.
- The dead man's handle (MCH) must stay in horizontal position while moving — if the driver's grip releases and speed is ≥5 kmph, the dead-man device activates automatically.
Neutral Section Negotiation (ENS)
At 250 metres from the neutral section, the motorman presses the ENS button for 2–3 seconds. The button's backlight flashes until the first Motor Coach's VCB trips, then glows steadily until all basic units have passed through — after which VCBs close automatically. A red-background DDU message confirms the sequence has started.
Rescue Drive Mode (RDM)
If the TCN (Train Communication Network) fails, a TCN failure lamp glows. If V-max still shows a value, the train can continue working in a special RDM mode. If V-max shows zero force and the train won't move, the motorman switches fully into RDM: motor coaches are then controlled via hard-wired train lines instead of the network, commanding only Motoring/Braking at pre-configured TE/BE rates, with an overall speed restriction of 60 kmph. In RDM, the DDU may not function, Cruise Control is unavailable, and the dead-man's device can activate even at standstill.
Cab Changing Procedure
- Stop the train, apply auto brake (drop BP by 1.0 kg/cm²), confirm BC shows 1.2 kg/cm².
- Turn OFF and remove the ICS key (BIV); turn the DCS key (BL key) OFF — parking brake applies automatically when the DCS key is removed.
- In the new cab: turn ICS fully ON, insert and turn the DCS key ON — pilot lamps glow then extinguish; confirm cab occupancy shows blue, BP is charged, and BC drops to 0.8 kg/cm² (holding brake) before releasing parking brake and taking traction.
Joint Brake Test (JBT)
A coordinated motorman-guard check before departure: the guard confirms 5-bell signals at each stage as the motorman creates 0.7 kg/cm² then 1.2 kg/cm² BC pressure via the controller, the guard drops BP fully via the emergency brake valve to confirm auto-brake response, then both confirm BP restored to 5 kg/cm² and BC back to 0 before giving 5 bells to complete the test.