How is the Type 179 controller specification similar to the 170 specification?

The Type 179 controller specification is similar to the 170 specification primarily due to its open architecture and the allowance for interchangeability of components. This design philosophy promotes flexibility in how the controllers can be configured and integrated with various components. The open architecture means that users can mix and match different components from multiple manufacturers, enhancing system adaptability and allowing for upgrades or repairs without being constrained to a single vendor's products.

This interoperability is crucial for traffic signal systems, which often require updates and changes as technology evolves or as different traffic management strategies are implemented. The Type 179 controller, with its open architecture, facilitates smoother transitions and improvements in traffic signal infrastructure, similar to the capabilities of the 170 specification.

In contrast, factors such as housing design, compatibility with older controllers, and wiring configurations play less significant roles in distinguishing the similarities between these two specifications, particularly focusing on functionality and upgrade paths.