ESP2

ESP-2 was detached from its Keel Yoke Assembly (which remained in the Orbiter) and installed with the assistance of Space Shuttle Discovery’s robotic arm and two spacewalkers during the STS-114 mission. It is much larger than ESP-1 with eight FRAM sites creating room for up to eight spare parts (ORUs). Like ESP-1, it is powered by the Unity Module. However, unlike ESP-1, ESP-2 is attached to the Quest Joint Airlock using a specialized ESP Attachment Device (ESPAD). ESP-2 and ESP-3 are deployable versions of the integrated cargo carrier and have the same dimensions, approximately 8.5 feet (2.6 m) long and 14 feet (4.3 m) wide.

The ORUs on ESP-2 are:

• FRAM-1 (top side) Pump Module SN0005. Moved here robotically from ELC-2 on 6 March 2015 in a swap with failed Pump Module SN0004, which had been relocated here by the ISS-41 US EVA-27 crew in Oct. 2014
• FRAM-2 (top side) Direct Current Switching Unit (DCSU) (added by STS-123 crew) FRAM formerly held the VSSA
• FRAM-3 (top side) CTC-3 container moved here via SPDM. DCSU added by STS-123 crew) had been relocated via SPDM Jan. 30, 2013 to ELC-2.
• FRAM-4 (top side) Latching End Effector Support Equipment moved here via SPDM from ELC1.)Main Bus Switching Unit (MBSU) launched on ESP-2 moved to truss to replace a degraded unit which was brought inside and returned to earth on SpaceX CRS-12.
• FRAM-5 (keel side) Pitch/Roll Joint (P/R-J) added by STS-123 crew FRAM formerly held a CMG
• FRAM-6 (keel side) Main Bus Switching Unit (MBSU) added by STS-120 crew This unit was swapped with a failed unit MBSU #1 from the SO truss, by the Exp 32 crew in late 2012.
• FRAM-7 (keel side) Flex Hose Rotary Coupler (FHRC SN1003) launched on ESP-2
• FRAM-8 (keel side) Utility Transfer Assembly (UTA) launched on ESP-2