2x25kV TRACTION V-CONNECTED TRANSFORMER PROTECTION NUMERICAL CONTROL & RELAY PANEL
ALIND make Control & Relay (C&R) panel comes with the vertical self-supporting steel construction, low voltage, back-to-back duplex corridor type with central roofed-in access. The central access corridor is provided with lockable doors at either end.. The C&R panel is suitable for erection flush with the concrete floor by evenly spaced grounding bolts projecting through the base channels of its frame. The C&R panel is made in suitable sections to facilitate easy transport, handling and assembly at site. Lifting hooks are provided on the panel for loading of panel for transportation. The C&R panel as well as instrument and relay housings are dust and vermin-proof and is suitable for use in tropical humid climate. It have modular construction to facilitate ease of expansion and replacement. The instruments, control switches, push button, annunciation window, meters, mimic and indicating lamps are mounted on front side of the control panels. Equipment like protection relays, auxiliary relays etc. are provided on rear panels. The panel is fabricated from steel sheet of thickness greater than 3mm for front, rear, door panel and base panels, and greater than 2.0 mm for side, roof and doors. The bottom portion of the panel is provided with detachable type steel sheet covers (over trench portion) with suitable cable glands to facilitate entries of control cable from trenches to control panel. The sheet steel as well as other steel works are properly treated and then an under coat suitable to serve as base and binder before the finishing coat is applied. To avoid rusting of the panels during service, pre-treatment through seven-tank process are ensured prior to painting. There are provision provided for power down mode for the system when the substation is not being manned. In this case all the protection elements function as usual but the alarm, annunciation/display and local acknowledgement features will remain out of circuit till the system is activated again. A separate front accessible ON/OFF switch shall be provided for this purpose.