||NAVSO P-3641A: More Power For The Dollar
Appendix B. Design Review Checklists
for Power Systems and Power Supplies
- Was an adequate safety factor or design margin considered in all
- Is there adherence to standards for bend radii, crimping, soldering,
welding, brazing, etc., which are consistent with the application?
- Are adequate methods provided for packaging, mounting and cooling
components subject to performance degradation or reliability failure under a
worst-case thermal environment?
- Is redundancy provided in critical subsystems to ensure mission success?
- Is the use of unqualified mechanical components kept to a minimum?
- Are those components with storage life and/or operational life
restrictions kept to a minimum?
- Have protective measures been incorporated to prevent installation errors?
- Is there complete interface compatibility (mechanical-to-mechanical,
- Has protection from mechanical abuse by the use of suitable mechanical
protection techniques (packaging, mounting and structural) been incorporated?
- Has an adequate structural analysis (static and dynamic) been perfon-ned
on all equipment which contains or supports systems or subsystems?
- Have limited-life items been identified?
- Have assembly and chassis mounting locations been reviewed for shock and
- Has the design been reviewed for possible simplification?
- Have pins been provided to absorb shock and vibration loads between
assemblies and structures to prevent damage to mating connectors?
- Has the lowest-cost type of fabrication compatible with equipment
specification requirements been chosen? Are alternate construction and
"make-from" drawings applicable?
- Is the proper orientation of the unit for placement in its location made
obvious by its design or labeling?
- Does the arrangement of components follow a functional flow to preserve
- Have clamps, grommets, or other protective devices been employed to
protect wiring against damage?
- Do all screws have locking devices?
- Are all plug-in items secured with positive holding clamps?
- Are wires clamped so that terminals do not receive the strain of cable
- Have cantilevered brackets been eliminated?
- Have stiffening means or members been employed to achieve maximum rigidity
with minimum weight?
- Do wires have enough slack to permit relative motion between terminals
during shock and vibration without putting tension on the wire or wire
- Has a worst-case adverse tolerance buildup been performed for each
critical mechanical interface?
- Can close tolerances be broadened?
- Will tolerances remain within specified limits at extreme temperatures?
- Have standard fasteners been utilized throughout, with a major attempt at
minimizing sizes and types?
- Have proper fasteners been employed to satisfy EMI and drip-proof
- Do the quantity and strength of fasteners satisfy the functional
- Are fasteners which are used as structural members of sufficient size and
number to meet equipment requirements?
- For access doors and panels, are easily manipulated fasteners incorporated
in absolute minimum quantities?
- Are access door/panel fasteners captivated?
- For thread-type fasteners. has galling been addressed?
- Has adequate testing been proposed to demonstrate satisfactory operation
under simulated worst-case ambient conditions such as temperature, humidity,
shock, vibration, pressure, penetration/abrasion, ambient lighting, mounting
position, exposure (wind, rain, snow), sea state and operator skills?
- If the operating environment results in internal condensation, has a means
for draining, drying, or using a sealed system been included?
- Does vulnerable equipment have protection from dust, humidity, dirt,
contamination, salt spray, etc.?
- Have either of the following been utilized to enable equipment to
withstand the shock/vibration environment?
- Have any of the following corrosion techniques been utilized on exposed
- Corrosion resistant materials
- Plating and protective finishes
- Dissimilar metal contact avoidance
- Environmental control (water entrapment prevention, atmospheric moisture
- Has electrolytic action under specification extremes of humidity and
temperature been minimized?
- Have questionable areas been analyzed for shock or vibration?
- Are heavy components mounted as low as possible to keep center of gravity
sufficiently low to meet shock and vibration requirements?
- Are components spaced and rigidly held so as to prevent contact with each
other during shock or vibration?
- When adhesives are used, are the adhesives selected based on environment
and materials which they are bonding?
- Are the materials selected for fabrication compatible with the strength,
weight, electrical stress factors, specified environment and lowest cost of
the finished component?
- Are all materials corrosive-resistant, nonflammable and nontoxic?
- Has a thorough thermal analysis determined that component operating
temperatures and ambient temperatures will not exceed specified derated
maximums (as applicable)?
- Are sufficient air openings and heat paths provided to satisfy cooling
- Are heat-sensitive components isolated from hot spots?
- Have heat sinks and heat dissipation devices been utilized?
- Has sufficient space been left between resistors and other heat-producing
or heat-sensitive components?
- Has heat dissipation been considered for both peak and average conditions?
- Has the unit been designed to function at maximum operating temperature
for peak and average conditions?