we had a project done recently,

We have used 5 watts bulb.
Total of 235 no.s
voltage -240v

Wires used- 0.75mm duplex stranded cables and 1.5mm 3core cables, 8mm pvc connector
I need to find the electrical load calculation for the above job.

Would be really appreciable if I get the ans.
I have calculated the total amps. req.
Total watts/voltage = 1175/240=4.8958 amp

Please verify - the 5 watt lamps are all wired in parallel to the 240V power supply - correct? You have already calculated the load due to the lamps, so what else do you need? If you want to calculate loss due to resistance of the wiring you will need to be much more specific as to how the lamps are wired - how much current is flowing through each section of wiring and the length of each sections as well. Using 0.75 mm wire means you have resistance in the wires of about 0.033 ohms/meter of cable; from that you should be able to calculate I^2R heating loss.