DDU USER MANUAL V5.0
The first graphic mimic in the second row shows the loco type and loco number at bottom, the
active cab and the direction selected. The active cab is indicated by a small green dot and the
arrow indicates the direction selected. The second graphic mimic displays the status of
pantograph. A block arrow is used to represent the pantograph. When both the pantographs
are down, the arrow looks down in grey colour. When any one panto is raised, the arrow
points upwards with green colour.
The VCB is represented by three-line segments. The notation used is similar to the one used for
opening and closing the VCB at OHE neutral sections. When the VCB is OFF, the upper- and
lower-line segments are vertical, middle segment is horizontal and the colour is grey. When the
VCB is closed, all the three-line segments become vertical with green colour.
Right of the VCB mimic is the area for displaying input power and line frequency. Input power
displays the instantaneous power at pantograph, calculated by ALG in kW. The Line frequency is
also measured by ALG in Hz. In the second-row right side is the sub-system status. There are 19
subsystems in three phase locomotives. The sub-system 20 does not exist and is retained for
getting symmetry of the screen but always remain in grey colour. If a sub-system is isolated, the
colour will change to red. A healthy sub-system will be in green colour. For getting the name of
the sub-system, Screen-2 can be activated.
The third row is split into two vertical halves. The left portion has three verticals meters viz.
TE/BE, Catenary Voltage & Primary Current. The TE/BE meter provides demand (W) set on left
side. Actual (X) value realised is shown on the right side, which is a very good scale for
comparison. The actual numerical value appears at the bottom. Please note that during bad
track conditions, Demand (W) and Actual (X) can vary widely, especially during wheel slip
conditions.
The primary current is shown in a 0 to 300A scale.
The right half side of row 3 of the display is again split into two horizontal portions. The upper
portion shows the speedometer mimic. The driver display reads the loco type from the MVB
(WAG9/WAG9H/WAP7/WAP5) and accordingly adjusts the maximum speed limit range. The
portion up to the maximum limit is shown in green colour and above the speed limit is shown in
red colour. In WAG9/9H locomotives, the speed limit is 100 km/h and in WAP5/WAP7, the
speed limit is 130 km/h. These figures are automatically adjusted based on the loco type. The
numerical value of the speed in km/h is displayed at the bottom.
In the right side of the speedometer dial area, an indication is given for the constant speed
operation. When driver presses the constant speed button BPCS, this indication turns green.
When not in constant speed mode, the colour is grey. Within the same speedometer dial area
right bottom corner, an indication for wheel slip (LSP) is provided. When there is wheel slip, this
indication turns orange, otherwise, the colour is grey.
Below the speedometer dial, four process variables are displayed viz. battery, BC, MR & BP.
