ABB ACH550 HVAC Drive Fully-Functional Demonstration System E-Clipse Training Case These are beautifully constructed. They are in excellent condition and fully functional. What you see in the photos is what you will receive. We are wholesaler/liquidators and not HVAC specialists. Our knowledge on these is very limited. Please look at the photos carefully. What you see is what you will receive. Brief description of the ACH550 legacy HVAC drive: (From ABB's Website) Your HVAC system demands effortless comfort for everyone. Our intelligent variable speed drive is dedicated to saving energy, producing quality air, and alleviating environmental concerns. Reduce costs by controlling your building?s fans, compressors, and pump motors efficiently, for an energy conscious commercial environment. The ACH550 provides proven reliability, flexibility, and every essential HVAC communication protocol. It is pre-programmed for several applications, including: air handling units, cooling towers, chillers, and more. Highlights: Embedded BACnet Interactive startup assistant Tailor made HVAC software Two built-in PID controllers Real time clock and calendar Built-in timers Harmonic mitigation built-in Thanks for looking at our listing and supporting our small family business! SHELF: WH-A(bottom shelf)