Every Warframe is built with a concept as a foundation upon which its appearance and kit are designed.
In the specific case of what you want, you would need a concept that would justify a Warframe being unable to constantly function at 100%.
For me personally, with this requirement, two concepts come to my mind:
Nuclear reactor: If it goes at full power for too long, it bursts, leaving the entire area unavoidable and destroyed
Siege gunner: In this case it would be a Warframe that due to the wars would have lost much of its original capabilities and depended on external machinery to develop its functions, the ability to bring a customized necramech to the battlefield included (Basically Ironman + Perturabo made Warframe)