Multiple software agents can be used to perform the real-time control of electrical grids. The control performance of such solutions is influenced by software non-idealities such as crashes and delays of the software agents, and message losses and delays due to the underlying communication network. To study the effect of these non-idealities on control systems, we present an open-source software testbed, named T-RECS. It uses software containers to test existing software without modification. The communication network among the software containers is emulated using Mininet framework, which allows for real packets being exchanged. The electric resources in the grid are simulated using state-of-the-art models, whereas the grid itself is modeled in the phasor domain. As control agents are run as is and message exchanges are emulated, T-RECS accurately captures the real-world properties of the control framework. We demonstrate the working of T-RECS with the Commelec control framework and show the effect of network non-idealities on the control performance. We make a beta version available.