Regulating agencies mandate that model verification of power system components must be performed to make sure the system analysis software perform accurately. Such verification is necessary for series compensation devices used in transmission systems, since they deteriorate due to aging or prolonged subjection to stressed condition, leading to changes in compensation levels or voltage-current characteristic of the metal oxide varistor (MOV) protecting them. This paper presents a method that uses synchronized time-domain data captured by intelligent electronic devices (IEDs) at both ends of a line for model verification of a fixed series compensation device installed at one location in the line. Electromagnetic transient line model is used to calculate the current and voltage across the compensation device, which in turn are used to determine the actual compensation and the actual voltage-current characteristic of MOV. These characteristics are used to detect failures in MOV and spark-gap. PSCAD/EMTDC is used to test the method.