It is very common to model an industrial sub-process transfer function by FOPDT. TOPDT models are also found in some situations as an appropriate model. A third-order transfer function composed of three first-order processes in series with delay function composes TOPDT. Scanty information is available for controller tuning techniques of TOPDT process. In present analysis, starting with the TOPDT model, converting it to SOPDT and then to FOPDT, controllers are designed using Integral error-based tuning techniques. Controllers are analyzed for their set-point tracking capacity.