SSP_57000_Revision_S.docx

SSP 57000 January 2018 Revision S Pressurized Payloads Interface Requirements Document

International Space Station Program

Revision S - ERRATA

January 2018

Type 4

EXPORT CONTROLLED - This technology or software is subject to the U.S. Export Administration Regulations (EAR, 15 C.F.R. Parts 730-774). No authorization from the U.S. Department of Commerce is required for export, re-export, in-country transfer, or access EXCEPT to country group E:1 or E:2 countries/persons per Supp.1 to Part 740 of the EAR/ECCN EAR99.

esa european space agency

National Aeronautics and Space Administration International Space Station Program Johnson Space Center Houston, Texas Contract No. NAS15-10000 CAGE Code 2B945

SSP 57000

SSP 57000

Revision P

REVISION AND HISTORY PAGE

DATE

57000-NA-0008B, 57000-NA-0011B, 57000-NA-0018A, 57000-NA-0019B, 57000-NA-0021A, 57000-NA-0027A, 57000-NA-0028A, 57000-NA-0030A, 57000-NA-0032, 57000-NA-0033, 57000-NA-0034A, 57000-NA-0035, 57000-NA-0036, 57000-NA-0038A, 57000-NA-0040A, 57000-NA-0044A

02-18-98

57000-NA-0007C, 57000-NA-0009D, 57000-NA-0010B, 57000-NA-0012C, 57000-NA-0013B, 57000-NA-0014C, 57000-NA-0015C, 57000-NA-0016B, 57000-NA-0017C, 57000-NA-0020A, 57000-NA-0022C, 57000-NA-0024D, 57000-NA-0026B, 57000-NA-0029E, 57000-NA-0031B, 57000-NA-0039C, 57000-NA-0041C, 57000-NA-0042A, 57000-NA-0043A, 57000-NA-0045B, 57000-NA-0047, 57000-NA-0048, 57000-NA-0049A, 57000-NA-0050A, 57000-NA-0051A, 57000-NA-0052A, 57000-NA-0053A, 57000-NA-0054B, 57000-NA-0055, 57000-NA-0056, 57000-NA-0057C, 57000-NA-0058, 57000-NA-0059, 57000-NA-0060A, 57000-NA-0061, 57000-NA-0062, 57000-NA-0063B, 57000-NA-0064B, 57000-NA-0065, 57000-NA-0066B, 57000-NA-0067, 57000-NA-0068B, 57000-NA-0069A, 57000-NA-0070A, 57000-NA-0071A, 57000-NA-0072A, 57000-NA-0073A, 57000-NA-0074A, 57000-NA-0075, 57000-NA-0076B, 57000-NA-0077, 57000-NA-0078A, 57000-NA-0079A, 57000-NA-0080A, 57000-NA-0081A, 57000-NA-0082A, 57000-NA-0083A, 57000-NA-0084, 57000-NA-0085A, 57000-NA-0087, 57000-NA-0088A, 57000-NA-0089A, 57000-NA-0090, 57000-NA-0091A, 57000-NA-0092A, 57000-NA-0093A, 57000-NA-0096A, 57000-NA-0097, 57000-NA-0098A, 57000-NA-0099A, 57000-NA-0100B, 57000-NA-0101C, 57000-NA-0102, 57000-NA-0103B, 57000-NA-0104C, 57000-NA-0105, 57000-NA-0106C, 57000-NA-0107A, 57000-NA-0108

11-04-98

57000-NA-0109B, 57000-NA-0111A, 57000-NA-0112A, 57000-NA-0113, 57000-NA-114D, 57000-NA-0115A, 57000-NA-0116C, 57000-NA-0117A, 57000-NA-0119B, 57000-NA-0120, 57000-NA-0121B, 57000-NA-122D, 57000-NA-0123A, 57000-NA-0126C, 57000-NA-0127B, 57000-NA-0128A, 57000-NA-0129A, 57000-NA-0130, 57000-NA-0131A, 57000-NA-0133A, 57000-NA-0135H, 57000-NA-136C, 57000-NA-0137, 07-08-99

57000-NA-0132D, 57000-NA-0139B, 57000-NA-0140A, 57000-NA-141,

57000-NA-0143A, 57000-NA-0146A, 57000-NA-0147A, 57000-NA-149,

57000-NA-0150C, 57000-NA-0152A, 57000-NA-0153, 57000-NA-154,

57000-NA-0155, 57000-NA-0156A, 57000-NA-0157A, 57000-NA-0158,

57000-NA-0159, 57000-NA-0160, 57000-NA-0162A, 57000-NA-0163A,

57000-NA-164B, 57000-NA-0165A, 57000-NA-0166B, 57000-NA-0167,

57000-NA-0168B, 57000-NA-0170, 57000-NA-0174A, 57000-NA-0177A

11-16-99

57000-NA-0151H, 57000-NA-0161C, 57000-NA-0179, 57000-NA-0180,

57000-NA-0181C, 57000-NA-0182, 57000-NA-0183A, 57000-NA-0184A, 57000-NA-0185A, 57000-NA-0189, 57000-NA-0190B, 57000-NA-0191A, 57000-NA-0192, 57000-NA-0193B, 57000-NA-0194, 57000-NA-0195E, 57000-NA-0196, 57000-NA-0202, 57000-ES-0001A, 57000-ND-0003C

4-18-01

SSCD 003970 incorporates PIRN 57000-NA-0205A SSCD 004176 incorporates PIRNS 57000-NA-0198A, 57000-NA-0203, 57000-NA-0208, 57000-NA-0222, 57000-NA-0235A

11-20-01

Revision E IRN 0002 is the first release on the IPIC Contract.

07-30-03

SSCD 005453 R1 incorporates PIRNs 57000-NA-0134F, 57000-NA-0175C SSCD 006251 R1 incorporates PIRNs 57000-NA-0148B, 57000-NA-0176H, 57000-NA-0238A, 57000-NA-0241D, 57000-NA-0242, 57000-NA-0252C, 57000-NA-0255, 57000-NA-0258A, 57000-NA-0265 SSCD 006892 R2 incorporates PIRNs 57000-NA-0197D, 57000-NA-0253D, 57000-NA-0254B, 57000-NA-0260B, 57000-NA-0267, 57000-NA-0269B 07-31-03

Revision G incorporates the following PIRNs:

57000-NA-0188B, 57000-NA-0272A, 57000-NA-0273A,

57000-NA-0274A, 57000-NA-0276E, 57000-NA-0277D,

57000-NA-0278D, 57000-NA-0279, 57000-NA-0285,

57000-NA-0287B, 57000-ND-0005

11-19-03

Revision G incorporates the following PIRNs:

57000-NA-0188B, 57000-NA-0272A, 57000-NA-0273A,

57000-NA-0274A, 57000-NA-0276E, 57000-NA-0277D,

57000-NA-0278D, 57000-NA-0279, 57000-NA-0285,

57000-NA-0287B, 57000-ND-0005

Rev G closes SSCN 001510 which was incorporated by PIRN 57000-NA-0146A in Revision D.

Rev G closes SSCN 002581 which was incorporated by PIRNs 57000-NA-0184A & 5700-NA-0185A in Revision E.

Rev G closes SSCN 003410 which was incorporated by PIRN 57000-NA-0223D in IRN 0002.

Rev G closes SSCN 003928 which was incorporated by PIRN 57000-NA-0253D in Revision F.

Rev G closes SSCN 005389 which was incorporated by PIRN 57000-NA-0254B in Revision F.

08-24-04

Early Release Revision H incorporates the following PIRNs:

57000-NA-0264B, 57000-NA-0271B, 57000-NA-0284B,57000-NA-0286,

57000-NA-0288B, 57000-NA-0289C,57000-NA-0290, 57000-NA-0291B,

57000-NA-0292A,57000-NA-0293B, 57000-NA-0294B, 57000-NA-0295C, 57000-NA-0296A, 57000-NA-0297A, 57000-NA-0298,57000-NA-0299, 57000-NA-0300C, 57000-NA-0301C,57000-NA-0305D, 57000-NA-0306, 57000-NA-0307 57000-NA-0308A, 57000-NA-0310D, 57000-NA-0311A, 57000-NA-0313, 57000-NA-0314A, 57000-NA-0315A, 57000-NA-0316, 57000-NA-0317, 57000-NA-0318A, 57000-NA-0319C, 57000-NA-0320A, 57000-NA-0321A, 57000-NA-0323, 57000-NA-0324B, 57000-NA-0325A, 57000-NA-0326A, 57000-NA-0327 11-16-07

Rev H closes SSCN 002664 which was incorporated by PIRN 57000-NA-0286 in Revision H.

Rev H closes SSCN 005144 which was incorporated by PIRN 57000-NA-0264B in Revision H.

Rev H closes SSCN 008007 which was incorporated by PIRN 57000-NA-0297A in Revision H.

01-14-08

Revision J incorporates the following PIRNs 57000-NA-0204F, 57000-NA-0302B, 57000-NA-0303E, 57000-NA-0304B, 57000-NA-0309A, 57000-NA-0322A, 57000-NA-0328, 57000-NA-0329, 57000-NA-0331, 57000-NA-0332A, 57000-NA-0333, 57000-NA-0334A, 57000-NA-0336A, 57000-NA-0337A, 57000-NA-0338A, 57000-NA-0339A, 57000-NA-0340

08-19-09

Revision K incorporates the following PIRNs

57000-NA-0335B, 57000-NA-0341A, 57000-NA-0342, 57000-NA-0343,

57000-NA-0344C, 57000-NA-0345C, 57000-NA-0346, 57000-NA-0347,

57000-NA-0348A

07-20-10

Revision L incorporates the following PIRNs

57000-NA-0330A, 57000-NA-0349, 57000-NA-0350B, 57000-NA-0351A, 57000-NA-0353A

07-08-11

Revision M incorporates the following PIRNs

57000-NA-0221C, 57000-NA-0354A, 57000-NA-0355, 57000-NA-0356A, 57000-NA-0358

08-13-12

Revision N incorporates the following PIRNs

57000-NA-0359, 57000-NA-0360A, 57000-NA-0361, 57000-NA-0362A,

57000-NA-0364C, 57000-NA-0365, 57000-NA-0366, 57000-NA-0367,

57000-NA-0369A, 57000-NA-0370

08-09-13

Revision P incorporates the following PIRNs 57000-NA-0352C, 57000-NA-0363C, (SSCN 012929) with

PIRN 57000-NA-0363C, 57000-NA-0373B, 57000-NA-0374A,

57000-NA-0375, 57000-NA-0376, 57000-NA-0377, 57000-NA-0378,

57001-NA-0096B

11-12-14

Revision R is a total document update.

06-22-16

Revision S incorporates the following PIRNs 57000-IRD-PIRN-0001A, 57000-IRD-PIRN-0002B, 57000-IRD-PIRN-0003C, 57000-IRD-PIRN-0004, 57000-IRD-PIRN-0005A, 57000-IRD-PIRN-0006, 57000-IRD-PIRN-0007, 57000-IRD-PIRN-0008, 57000-IRD-PIRN-0009, 57000-IRD-PIRN-0011A, 57000-IRD-PIRN-0012, 57000-IRD-PIRN-0013, 57000-IRD-PIRN-0014, 57000-IRD-PIRN-0015, 57000-IRD-PIRN-0016, 57000-IRD-PIRN-0018, 57000-IRD-PIRN-0019, 57000-IRD-PIRN-0022, 57000-IRD-PIRN-0023, 57000-IRD-PIRN-0025, 57000-IRD-PIRN-0026, 57000-IRD-PIRN-0027, 57000-IRD-PIRN-0028, 57000-IRD-PIRN-0029, 57000-IRD-PIRN-0030

10-03-18

ERU: /s/ S. Phillips 10-03-18

PREFACE

This document defines sets of requirements that apply to International Space Station (ISS) pressurized volume payloads, dependent on their interfaces and design. The requirements in this document address launch/ascent, on-orbit, and descent/return physical interfaces and environments. This document is under the control of the Space Station Program Control Board (SSPCB). Any changes or revisions to this document will be delegated to the Multilateral Vehicle Control Board (MVCB) for approval.

ISS PROGRAM / PARTNER CONCURRENCE

4/10/18

Dana J. Weigel, Manager, Vehicle Office, NASA OB

Date

6/26/18

Bernardo Patti, Head of the Exploration Group, Directorate of Human & Robotic Exploration Programmes

Date

DOCUMENT CONCURRENCE

TABLE OF CONTENTS

Appendices

SSP 57000 January 2018 Revision S vi Export Controlled – EAR/ECCN EAR99 Introduction Purpose This Interface Requirements Document (IRD) is the principle source for interface design requirements for all National Aeronautics and Space Administration (NASA) developed payloads operating in the pressurized volume of the ISS, and for ESA and JAXA payloads operated in the USOS (all non-Russian modules except JEM and Columbus). Payload developers must verify the applicable requirements in this document to ensure the safety of the ISS crew, transport vehicles, on-orbit ISS systems hardware, and neighboring payloads. This document also provides design guidance that ensures the basic operation of the payload and affects the payload’s mission success. It is the responsibility of the payload developer (PD) to design in accordance with the design guidance. ESA and JAXA payloads operated in their modules follow COL-RIBRE-SPE-0164 and NASDA-ESPC-2898, JPAH Vol. 1, respectively.

Scope This document applies to all pressurized volume payloads, including sortie payloads which launch and return on the same transport vehicle and never transfer to the ISS, and any unpressurized payloads that launch in the pressurized volume of a transport vehicle. This document also applies to crossover payloads which transfer to the ISS for science operations and return on the same transport vehicle. Payloads that transfer outside the ISS from the pressurized volume must also meet all applicable requirements from SSP 57003, External Payload Interface Requirements Document. Command and Data Handling (C&DH) interface requirements in this document also apply to NASA- developed Japanese Experiment Module (JEM) Exposed Facility (EF) and Columbus (COL) Exposed Payload Facility (EPF) payloads. This document does not include interface requirements for the Russian partner modules.

This document addresses transportation requirements for payloads that are passively stowed in the Russian Space Agency (RSA) Progress or Soyuz, the Japan Aerospace Exploration Agency (JAXA) H-IIB Transfer Vehicle (HTV), the Space Exploration Technologies (SpaceX) Dragon, and the Orbital ATK Cygnus vehicles. This document also addresses transportation requirements for powered payloads that are hard mounted middeck lockers in the SpaceX Dragon and the Orbital ATK Cygnus vehicles. Pressurized payload power is only available on these two launch vehicles.

Use This document provides interface design and verification requirements on ISS pressurized payloads and also provides interface design guidance necessary for the successful operation of the payload. The PD must also provide data deliverables applicable to their payload’s design. These requirements, guidelines, and data deliverables are allocated to a payload through the payload unique ICD. The PD and the ISS Program must jointly agree on the interfaces and identify requirements as applicable if the interface exists, and not applicable if the interface does not exist for the payload configuration documented in the ICD. This applies to physical and environmental interfaces. For requirements where exceptions are required because the payload will not meet an applicable requirement, the PD must provide an exception request to the ISS Program for evaluation. Implementation of design guidance is the responsibility of the PD as part of the payload’s internal development and verification campaign. Resource allocations such as electric power or coolant are given as design guidelines (notated as “should”). When the total requested resource value exceeds the module capability, operational constraints may be applied.

All payloads must assess the general requirements in Sections 3.0 and 4.0. Depending on their transportation configuration and on-orbit configuration, a payload will have to assess requirements from at least one of the appendices. Each appendix has a Section 3 and Section 4, with requirements/guidelines and verification respectively, but with the appendix letter appended in front (for example, N.3.5.1 and N.4.3.5.1). Note that some appendices have requirement pointers to select requirements in other appendices within this book (for example, an EXPRESS subrack payload might be directed to Appendix N for Integrated Racks). This is done to avoid duplication of a requirement.

Control And Maintenance This IRD is controlled through the authority of the Multilateral Vehicle Control Board (MVCB). Changes to this IRD are made using the Preliminary Interface Revision Notice (PIRN) process. For the purposes of Certification of Flight Readiness (CoFR), PIRNs are applicable when the final signature is received from NASA.

SSP 57000 January 2018 Revision S

2-1 Export Controlled – EAR/ECCN EAR99 Documentation Applicable and reference documents can be found in Section 5.0.

Payload Interface Requirements And Guidance This document provides requirements, guidance, and information to be used by the payload developer to successfully integrate a payload into the ISS systems. This IRD includes several informational pointers to requirements in SSP 51700, Payload Safety Policy and Requirements for the International Space Station. These requirements are handled through the safety process. This IRD does not include a complete set of those safety requirements.

Unless specified as applicable to the USL, JEM, or COL, a requirement is applicable in all ISS modules except the Russian Segment.

Verification of Program Furnished Equipment by the Payload Developer is not required. However, the integrated experiment assembly, using Program Furnished Equipment, does need to be verified.

Responsibilities of the payload developer are allocated as follows:

Structural/Mechanical, Microgravity, Angular Momentum Disturbance, And Protrusion Interface Requirements Structural/Mechanical Loads Requirements On-Orbit Loads Payloads should provide positive margins of safety for on-orbit loads of 0.2 g acting in any direction.

Crew-Induced Loads Payload structures that have been judged by the ISRP to be safety-critical shall (and other payload structures should) provide positive margins of safety when exposed to the crew-induced loads defined in Table 3.1.1.1.2-1. Items mounted to a Bogen Arm or that are handheld/worn are exempt from this requirement.

TABLE 3.1.1.1.2-1 CREW-INDUCED LOADS

(50 lbf), limit Any direction

(125 lbf), limit Any direction

Legend:

ft = feet, m = meter, N = Newton, lbf = pounds force

Seat Track Allowable Loads And Moments

TABLE 3.1.1.1.3-1 USL/JEM MODULE AND SYSTEM RACK AND NASA/JAXA PAYLOAD RACK SEAT TRACK ALLOWABLE LOADS AND MOMENTS

USL/JEM MODULE AND SYSTEM RACKS AND NASA/JAXA PAYLOAD RACKS

FIGURE 3.1.1.1.3-1 SEAT TRACK ORIENTATION

B. Payloads mounted to the seat tracks of the COL deck system racks or ESA payload racks shall limit loads and moments to less than the values shown in Table 3.1.1.1.3-2 for each individual axis, as well as the RSS values. X/Y/Z directions with respect to the seat track are shown in Figure 3.1.1.1.3-1. These limits pertain to the seat track only, and only at a single attach point. They do not account for the effect of multiple attachment points to the seat track. As a general guideline, a spacing of 20 inches between seat track attachment points will minimize the interaction between load points. The limits in the table below assume that the attachment payload has two studs engaging the track.

Note: This requirement also applies to payloads mounting to ESA payload racks in the USL or JEM.

TABLE 3.1.1.1.3-2 COL SYSTEM RACK AND ESA PAYLOAD RACK SEAT TRACK ALLOWABLE LOADS AND MOMENTS

Columbus Deck System Racks (COL1D1, COL1D2, COL1D3)

ESA PAYLOAD RACKS

The allowable loads and moments for the ESA payloads racks must be addressed on a case-by-case basis.

Portable Fire Extinguisher Discharge Payloads with Portable Fire Extinguisher (PFE) access ports shall maintain positive margins of safety in accordance with SSP 52005 when exposed to the PFE discharge rate shown in Figure 3.1.1.2-1.

SSP 57000 January 2018

3-4 Export Controlled - EAR/ECCN EAR99

FIGURE 3.1.1.2-1 MANUAL FIRE SUPPRESSION SYSTEM PERFORMANCE CHARACTERISTICS AT THE RACK I/F

SSP 57000 January 2018

3-5 Export Compliance – see Title Page 3-5 Export Compliance – see Title Page 3-5 Export Compliance – see Title Page 3-5 Export Compliance – see Title Page 3-5 Export Controlled – EAR/ECCN EAR99

Overpressure Relief Device Payloads that have an overpressure relief device(s) shall not vent that device directly into the cabin aisle-way.

Window Protection Optical instruments and payloads (camera lenses, telescopes, binoculars, etc.) that are handheld and intended for use with any ISS window shall incorporate bumper rings on the front, entrance pupil end of the lens that are coated with a flat black, matte finish, polyvinyl chloride (PVC) [Plastisol] coating (e.g. PolyOne Corporation’s Material DB2656B Black, Product Code FO00003723EV, utilized by U.S. Plastic Coatings Corporation) at least 1.524 mm (0.06 inch) thick to prevent damage to the window panes. Payloads that are designed to be secured/mounted to the WORF facility on the WORF rack payload support shelf prior to retraction of the WORF Bump Shield or opening of the AgCam/ISSAC Bump Shield Door utilizing mounts other than the WORF Small Camera Bracket (SCB) that have hard stops to prevent lenses from entering the 1.27 cm (0.5 inch) Keep Out Zone (KOZ) of the inboard surface of the primary pressure pane of the window are exempt from this requirement.

Securing Of Threaded Fasteners Payload threaded fasteners that have been judged by the ISRP to perform a safety-critical function shall (and other payload threaded fasteners should) incorporate two separate verifiable locking features. (Reference SSP 52005, Section 5.6, Fastener Requirements).

Design Guidance: Threaded inserts must be used in applications that require tapped holes in aluminum, magnesium, plastics, or other materials that are susceptible to galling or thread damage. When self-locking features are used, the screw length must be sufficient to fully engage the locking device with a minimum of two thread protrusion through the locking mechanism. When self-locking devices are used, an allowable range of running torque, or the maximum number of reuses that would still ensure an adequate lock, must be specified. Spring-type or star-type lock washers must not be used. Adjustable fittings or mounting plates which use oversized holes or slotted holes to provide adjustment must not be dependent upon friction between the fitting or mounting plate and the mounting surface to provide locking. Diamond-type serrations must not be used. Random vibrating testing of the as-used configuration may not be used to justify an exception to this requirement.

DELETED

Microgravity Microgravity requirements for EXPRESS subrack payloads, non-rack payloads, and integrated racks are addressed in their respective appendices.

Limit Angular Momentum Disturbance Limit Disturbance Induced Iss Attitude Rate Payloads with individual rotating parts with a mass greater than 2 kg or with rotating parts that gimbal shall limit any non-transitory disturbance (disturbance duration greater than 10 seconds) induced on the on-orbit Space Station by an individual disturbance source to an angular momentum impulse of less than the per axis values shown in Table 3.1.3.1-1 during any continuous nine minute period. Any non-transitory disturbance source that generates a total angular momentum impulse less than 100 ft-lb-sec (135 N-m-sec) in a 110 minute period can be ignored with respect to this requirement.

Table 3.1.3.1-1 MAXIMUM ANGULAR MOMENTUM IMPULSE

Note:

(1) Where Hx, Hy, and Hz are the absolute values of the x, y, and z components of the disturbance angular momentum impulse relative to the Assembly Complete center of mass, XISS = -17.66 ft (-5.38m); YISS = -1.32 ft (-0.40 m); and ZISS = +14.80 ft (+4.51 m) in the Space Station Analysis Coordinate System, as defined in SSP 30219, Figure 4.0-1.

Limit Disturbance Induced Cmg Momentum Usage Payloads with individual rotating parts with a mass greater than 2 kg or with rotating parts that gimbal shall limit any disturbance (non-transitory or transitory) induced on the on-orbit Space Station by an individual disturbance source to an angular momentum impulse that produces an estimated Control Moment Gyroscope (CMG) momentum magnitude less than 10,000 ft-lb-sec (13,558 N-m-sec) during any continuous 110 minute period when evaluated per expression in Table 3.1.3.2-1. Any non-transitory disturbance source that generates a total angular momentum impulse less than 100 ft-lb-sec (135 N-m-sec) in a 110 minute period can be ignored with respect to this requirement.

Table 3.1.3.2-1 CMG MOMENTUM USAGE CALCULATION

Estimated CMG Momentum Usage ft·lb·sec

N·m·sec

Notes:

1. Where Hx, Hy, and Hz are the absolute values of the x, y, and z components of the disturbance angular momentum impulse using the Assembly Complete center of mass, XISS = -17.66 ft (5.38 m); YISS = -1.32 ft (-0.40 m); and ZISS = +14.80 ft (+4.51 m) in the Space Station Analysis Coordinate System, as defined in SSP 30219, Figure 4.0-1.

2. Where 1069, 6885, and 779 ft·lb·sec (and 1449, 9334, and 1056 N·m·sec) are the x, y, and z components, respectively, of the CMG angular momentum allocation for environmental disturbances.

Protrusions The ISS Program maintains crew egress and translations paths, and hardware clearance zones for the internal configuration of the ISS modules as specified in SSP 50261-01, Generic Groundrules, Requirements, and Constraints Part 1: Strategic and Tactical Planning, Section 3.12. These egress and translation paths, and clearance zones, are analyzed each increment using models of the ISS interior and models of the payload and system hardware protruding into, or mounted in, the aisles. These egress and translation paths may bend and curve along the length of the modules to avoid obstructions caused by payload and system equipment protruding from racks or being used in the aisle. Constraints are applied to payload hardware to ensure these paths are maintained as needed by planned operations. The egress paths and clearance zones include:

· Emergency Egress Path; 32 inches by 45 inches

· Crew Translation Path; 50 inches by 72 inches (USL, JEM, COL), 32 inches by 72 inches (other modules)

· Equipment Translation Path, 50 inches by 50 inches

· Visibility and access to critical equipment and controls

· Clearance around environmental control and life support equipment and functions

· Clearances to allow for rotation of adjacent racks

· Interferences with other payload or system hardware Constraints which may be associated with payload protrusions include:

· Removal of the protrusion during rack installation, equipment translation, and crew translation

· Removal of the protrusion if RMA is installed on the rack

· Removal of the protrusion to prevent interference with microgravity operations

· Removal or powering off of the payload if the protrusion blocks PFE access or the fire indicator

· Removal of the protrusion to eliminate interference with rack rotation(s)

· May limit the payload location

· May limit operation of the payload Protrusions have a negative impact on crew operations and are to be minimized. Violations of the translation paths and clearance zones of SSP 50261, Part 1, Section 3.12, which cannot be cleared through constraints may require a Program approved waiver before the payload can be used.

Protrusion Guidelines Non-permanent protrusions are for equipment that supports and/or provides the resources necessary to run an experiment, typically power/data cables and thermal hoses, and payload hardware which is typically left in place while in use, but does not interfere with crew restraints and mobility aids. Note that Paragraphs 3.12.4.1.6.2 and 3.12.4.2.1 require that payload hardware must be removable using hand operations and standard tools.

Protrusions designed to fit inside the envelope shown in Figure N.3.1.3-1 will generally avoid constraints.

Protrusion Data Requirements Data deliverable: Provide a dimensioned drawing or 3D CAD model (see Note 1) identifying all protrusions for on-orbit payload operations including the following:

· A dimensioned drawing of each configuration, if there are multiple operational configurations (including any temporary stowage configurations)

· The swing envelopes of any doors or pullout volumes for any drawers

· The motion path envelope for any hardware that requires deployment and actuation

· List any constraints for placement of the hardware in the aisle The drawing or model must identify each of the following (as applicable):

a) All PFE access ports

b) Payload power switch

c) Smoke indicator LED

d) All caution and warning labels For Subrack Payloads:

· At a minimum, provide dimensions from the payload surface that mates to the EXPRESS backplate, to the furthest extensions of the various protrusions (including cables (See Note 2)).

For Facility Payloads:

· At a minimum, provide dimensions from the lower left GSE boss plane to the furthest extension(s) of any protrusions (including cables (See Note 2)).

For Non-rack (Aisle-deployed) Payloads:

· The payload must attach to ISS structure at some point. Provide dimensions from that mating surface to the furthest extension(s) of the hardware setup (including cables (See Note 2)) and the means of attachment (hook and loop fastener, seat track, bungee cord, etc.)

Notes:

(2 pages)

inch (mm) Min Bend Radius inch (mm) Connectors/QDs

(20.64) 2.4 (60.96)

(20.64) 2.4 (60.96)

(20.64) 2.4 (60.96)

54.0 (1,371.6)

(4.67) 0.552 (14.02)

MS27467T15F35P

(Connector) M85049/36-14N05 (Backshell) J00026T2001 (RJ-45 Connector)

Data Cable - BER Only

(4.32) 1.00 (25.40) J00026T2001 (RJ-45 Connector) J00026T2001 (RJ-45 Connector)

(4.32) 1.00 (25.40)

(609.6)

(6.35) 0.75 (19.05) MS27467T17F6PN (Connector) (17 shell size) M85049/49-2-16 (Backshell) NB6GE14-4SNT (Connector) (14 shell size) NB-S-14 (Backshell)

38.0 (965.2)

(6.35) 0.75 (19.05)

(1,371.6)

(6.35) 0.75

(6.35) 0.75

MS3475L14-4S

(6.35) 0.75 (19.05)

MS3475L14-4S

(609.6)

(21.84) 4.00 (101.6)

(609.6)

(21.84) 4.00 (101.6)

(1,524.0)

(21.84) 4.00 (101.6)

(1,524.0)

(21.84) 4.00 (101.6)

MTL Coolant Hose (Supply) - Preece 78.0 (1981.2)

(21.84) 1.00 (25.40)

MTL Coolant Hose (Return) – Preece 78.0 (1981.2)

(21.84) 1.00 (25.40)

(977.9)

(35.13) 6.00 (152.4)

62.0 (1,574.8)

(35.13) 6.00 (152.4)

(1,625.6)

(17.78) 3.00 (76.2)

DELETED FROM TEMPLATE

Electrical Interface Requirements Electrical Power Characteristics Electrical power characteristics are specified in this section for two interfaces, Interfaces B and C, as depicted in Figure 3.2.1-1.

RPC

Integrated Rack Interface B

UIP

RPC

Portable Equipment Interface C

USL/JEM

UOP

RPC

UOP

RPC

Portable Equipment Interface C

COL

SUP

RPC

SUP

FIGURE 3.2.1-1 ELECTRICAL POWER INTERFACE LOCATIONS

Power Bus Isolation

Circuit Protection Circuit Protection Devices Overcurrent protection shall be provided at all points in the system where power is distributed to lower level (wire size not protected by upstream circuit protection device) feeder and branch lines in compliance with Table 3.2.1.2.1-1, Table 3.2.1.2.1-2, Table 3.2.1.2.1-3, Table 3.2.1.2.1-4, and Table 3.2.1.2.1-5.

Table 3.2.1.2.1-1 Fuse Derating

Rating at 25 °C ambient. Derating of fuses allows for loss of pressure, which lowers the blow current rating and allows for a decrease of current capability with time.(1)(3)

Fuse Derating Example:

The principal stress parameter is current:

A board expected to be operating at 90 °C ambient has a calculated maximum current of 1.0 A. The additional derating required due to temperature is calculated as shown:

The total derating factor is calculated as follows:

The fuse rating is calculated as shown:

A fuse with rating equal to or greater than 5.7 A is suitable in this circuit.

Table 3.2.1.2.1-2 Circuit Breaker Derating

Circuit breaker contacts are derated by multiplying the maximum rated contact current (resistive) by the appropriate contact derating factor.

(1) Use series resistance to ensure that circuits do not exceed the derated level.

Circuit Breaker Derating Example:

The principal stress parameter is contact current.

A circuit breaker is to be selected to control an electrical motor rated at 17 A, full load, 24 Vdc. The circuit breaker is to be installed in an environment with an ambient temperature ranging from 10 °C to 30 °C.

The temperature derating is:

The contact current derating is:

This example, then, requires the use of a circuit breaker with a maximum thermal rating equal to or greater than 50 °C and a maximum contact rating of at least 85 A for this application.

Table 3.2.1.2.1-3 Ambient Operating Temperature for Derating Relays and Switches

Temperature Extremes Under Which the Relay/Switch May Function

(1) The factors provided pertain only to contact loads, and they are intended for derating specified loads established in the governing specifications (resistive, inductive, motor, and/or lamp loads). The users are cautioned to use the contact voltages and nominal coil voltages (currents) prescribed in the governing specifications. Utilization of reduced coil voltages and abnormal contact voltages can potentially reduce the life of the relay and compromise relay operations.

The steps for relay/switch load derating are:

1. Select the appropriate load (resistive, inductive, motor, or lamp) and rating from the specification.

2. Determine the temperature range in the application. Select the appropriate factor from Table 3.2.1.2.1-3.

3. Determine the cycle rate in the application. Select the appropriate factor from Table 3.2.1.2.1-4.

4. Determine the load application. Select the appropriate factor from Table 3.2.1.2.1-5.

5. Calculate the derated load by multiplying the various factors together.

Derated Load = Load × Temp Factor × Cycle Rate Factor × Application Factor.

Other examples are as follows:

Example 1:

A 1.0 A relay is operated in an environment with a temperature range of +25 °C to +70 °C. The relay is cycled at a rate of 5 cycles per hour. The load application is make, break, and carry of a resistive load.

The worst case temperature is 70 °C. From Table 3.2.1.2.1-3 select 0.85.

The cycle rate is 5 cycles/hour. From Table 3.2.1.2.1-4 select 0.9.

The load application is specified as make, break, and carry. From Table 3.2.1.2.1-5 select 0.8.

Relay derating factor is 0.85 × 0.9 × 0.8 = 0.612. The derated contact load is 0.612 × 1.0 = 0.612 A resistive load.

Example 2:

A 10 A relay is operated in an environment with a temperature range of -40 °C to +35 °C. The relay is turned on for 3 minutes every 2 hours. The load application is carry only (resistive load).

From Table 3.2.1.2.1-3 select 0.85 From Table 3.2.1.2.1-4 select 0.85 From Table 3.2.1.2.1-5 select 1.5

Table 3.2.1.2.1-4 Cycle Rate per Hour for Derating Relays and Switches

Derating Factor for Nominal Cycle Rate

Cycle Rate Per Hour

(1) The factors provided pertain only to contact loads, and they are intended for derating specified loads established in the governing specifications (resistive, inductive, motor, and/or lamp loads). The users are cautioned to use the contact voltages and nominal coil voltages (currents) prescribed in the governing specifications. Utilization of reduced coil voltages and abnormal contact voltages can potentially reduce the life of the relay and compromise relay operations.

Table 3.2.1.2.1-5 Load Application Rate for Derating Relays and Switches

Wire Derating The payload wire derating scheme is shown in Figure 3.2.1.2.2-1.

Remote Power Controller Primary Circuit Protection Device Downstream EPCE Loads UIP or UOP or SUP EPCE use Table 3.2.1.2.2-1 Table 3.2.1.2.2-2 or Table 3.2.1.2.2-1 ISPR use 4 AWG per N.3.2.2.8.1

120 VDC

FIGURE 3.2.1.2.2-1 WIRE DERATING REQUIREMENTS FOR INTEGRATED RACKS

AND EPCE

Table 3.2.1.2.2-1 IVA Single Wire derating criteria

Wire Size

(AWG)

Maximum Nominal Allowed Single Wire Current (Isw), amperes1, 2, 3

Flow 7

(242 °F)

(352 °F)

33.0 °C (91.0 °F)

(242 °F)

(352 °F)

35.3 °C (95.0 °F)

(242 °F)

(352 °F)

35.3 °C (95.0 °F)

(242 °F)

(352 °F)

40.3 °C (104 °F)

(242 °F)

(352 °F)

40.3 °C (104 °F)

(242 °F)

(352 °F)

38.1 °C (100 °F)

(242 °F)

(352 °F)

37.5 °C (99 °F)

(242 °F)

(352 °F)

43.1 °C (109 °F)

(242 °F)

(352 °F)

48.7 °C (119 °F)

(242 °F)

(352 °F)

42.0 °C (107 °F)

(242 °F)

(352 °F)

49.8 °C (121 °F)

(242 °F)

(352 °F) 51 °C (123 °F)

(242 °F)

(352 °F)

50.4 °C5 (122 °F)

(242 °F)

(352 °F)

50.4 °C6 (122 °F)

1. These currents are for wires on-orbit in cabin ambient at 22 °C (72 °F).

2. Deratings listed are for wire rated for 200 °C maximum temperature.

3. Wire with these currents and temperatures are not to be accessible to the crew.

4. This current is the 130% maximum fault current for circuit protection devices.

5. Maximum current to limit wire touch temperature to 122 °F for size 2 wire is 150 A.

6. Maximum current to limit wire touch temperature to 122 °F for 1/0 size wire is 210 A.

7. Data from Figure 3 of SAE AS 50881 at 60,000 feet altitude

8. When wire is bundled, the maximum design current for each individual wire is derated according to the following:

Table 3.2.1.2.2-2 Current Carrying Capacity of Insulated Payload Wiring (Amperes) (From SSP 51700 (TA-92-038))

Notes:

1. Wire rating information is derived from extensive testing of MB0150-048 Orbiter wiring at JSC and applies to equivalent copper wiring with any type of insulation. For convenience, information pertaining to wire with insulation ratings of 150 °C, 175 °C, and 200 °C are shown. For wire ratings other than these, refer to JSC engineering publication TM 102179, “Selection of Wires and Circuit Protection Devices for NSTS Orbiter Vehicle Payload Electric Circuits”. Wire sizes smaller than 26 gauge are not recommended for use in payloads.

2. An ambient temperature of 22.2 °C is assumed for pressurized locations.

3. Current Carrying Capacity of Wire – Represents the maximum sustained current in amperes which the wire can carry in the specified environment and not experience a temperature that exceeds the temperature rating of the insulation material.

4. This table does not reflect wire bundle derating, nor does NASA JSC believe bundle derating to normally be necessary. This is due to the multitude of inter-related factors involved in bundling which can either enhance or degrade the current-carrying capacity of wire. However, in unique applications where a majority of wires in a bundle are heavily loaded simultaneously, the user may utilize the wire bundle criteria of Table 3.2.1.2.2-1, Note 8.

Loss Of Power SSP 51700, Paragraph 3.1.4.1 addresses Loss of Power.

Electrical Grounding And Isolation Adherence to the following requirements satisfies the ISS single point grounding scheme.

Payload Power…