W50S7T20Q0015_Questions and Answers dated 13Jul20.pdf

Questions & Answers received prior to 11 July 2020 Project: 182AW 400Hz Hangar Power

Solicitation # W50S7T20Q0015

1. QUESTION: The Description of the Requirement states the provided frequency converter is rated for 90 kva output. The Performance Work Statement states the frequency converter is rated for a 30 kva output. What is the correct output rating??

ANSWER: 30 kva is directed as a minimum by the aircraft specific technical data (T.O.’s). Current installed units have 60 kwa output. Market research performed by affected individuals yielded 90 kva as a common standard. Since this is a replacement I would say 60 kva should be the optimum.

2. QUESTION: The frequency converter will be installed inside Room 18 and remotely controlled from another location. The converter is specified to comply with Class 1 Division 1 explosion proof protection. If this is being installed in a room away from the remote control can it be provided as a NEMA 250 Type 3R or Type 1 enclosure?

ANSWER: The Class 1 division 1 explosion proofing is at the direction of the aircraft specific technical data for items in the designated hazardous area. Since the unit is remote, NEMA type 3R or 4 would suffice.

3. QUESTION: The existing remote control is to be connected to the new frequency converter. What manufacturer provided the existing remote control and frequency converter? Is there an available wiring diagram for the remote control?

ANSWER: Exisiting frequency converter is a Jetway Systems J-90-115 (input of 480v, 3ph, 60hz, 134a) (output 115v, 3ph, 400hz, 260a, 60kva) The remote is manufactured by J&B Aviation Services, inc. It controls power on/off, and raises/lowers the aircraft power attach cable. No wiring diagrams were provided.

4. QUESTION: Please can you kindly let me know if NEMA 3R or NEMA 4 is acceptable?

ANSWER: After looking into it, the need for the Class 1, Division 1 hazardous requirement is not necessary since the unit would be in a remote location, i.e. Room 18.

However, the weather tight characteristics of the 3R and 4 would still be preferential because of its proximity to the fire suppression system and tanks.

5. QUESTION: BETA.gov advertisement states “delivery and installation shall be accomplished within 59 days ARO”. Solid state frequency converters are not commercial off the shelf items but are typically built per order. Average lead time in our industry is 16 weeks. Will government accept a longer contract period, say 20 weeks, to allow for contract acceptance, issuance of subcontract PO to a manufacturer and shipment to be installed?

ANSWER: The Government is willing to accept a 20 week lead time to include installation. If a contractor is able to install a product in a quicker timeframe then the Government may consider this to be a better value.