Cone Calorimeter tests were performed on eight multi-conductor electrical cables. Measurements of ignition delay time, heat release rate, mass loss rate, and gas and smoke generation rates were made in the vertical (2 irradiance levels) and horizontal (3 irradiance levels) orientations. It was found that comparable ignition delay times were observed for all of the cross-linked polyolefin jacketed cables. The PVC jacketed cable had a substantially lower ignition delay time. All of the cables exhibited an ignition delay time dependence on external irradiance. Sample orientation did not significantly effect the ignition delay time. Heat release rate measurements showed that cables burned in multiple stages. Changes in the cable components actually burning were reflected in variations in mass loss, gas, and smoke generation rates as well as small changes in the effective heat of combustion HBr and HCl were detected during the burning of some of the cables. The production of HCN was detected at som point during the combustion of most of these cables.