Intepro Systems

Testing military ground & shipboard to MIL-STD-461G CS101

MIL-STD-461G CS101 is not a test of whether the equipment functions. It is a test of whether it can be upset — disturbance is injected deliberately onto the power leads and the equipment is watched for any change in behaviour. The subject here is vehicle electronics, shipboard converters, deployable power systems, running on 28 VDC, 270 VDC, 440 V 60 Hz shipboard, and the qualification being chased is survivability on a bus shared with motors, weapons and generators. What decides it is audio-frequency ripple injection, not anything the supply does at nominal. 400 Hz waveform synthesis belongs to a different document. Two things are needed: the injection chain, and series ripple injection across 30 Hz to 150 kHz via a coupling transformer, driven either by a signal generator and power amplifier chain or by a programmable source with built-in ripple and interharmonic injection. The EUT's own supply must be clean and fed through 50 µH LISNs, sized to the platform power type.

What you are testing

Device under test
vehicle electronics, shipboard converters, deployable power systems
Bus
28 VDC, 270 VDC, 440 V 60 Hz shipboard
Who buys this
defence primes and depot sustainment programmes

What MIL-STD-461G CS101 does not cover

  • 400 Hz waveform synthesis
  • reliability duration testing
  • grid ride-through
  • automotive voltage classes

If your programme needs those, they come from a different standard and often different hardware.

The limits this test has to reproduce

Ground and shipboard platforms live on the DC side of this standard. The 400 Hz AC clauses are not your test — the 28 V and 270 V bus behaviour is.

ParameterValueClause
Frequency range30 Hz – 150 kHzCS101
ApplicabilityAC inputs ≤30 A per phase and all DC inputsCS101
Limit Curve #2126 dBµV (≈2.0 V RMS) for nominal source voltage ≤28 VCS101 Figure
Alternative compliance80 W into 0.5 Ω precalibrated, falling to 0.09 W at 150 kHzCS101
EUT power feedThrough 50 µH LISNs§4.3.6

The clauses military programmes actually face, as published in MIL-STD-461G CS101, revision G, 11 December 2015. See every limit in MIL-STD-461G CS101. Certification work should be run against the published standard.

What decides the rig here

The requirements that separate a system that can run this programme from one that only meets the headline numbers.

No 400 Hz means no aircraft source

Buying an aviation-grade AC source for a ground platform is a common and expensive mis-spec. The DC clauses are the requirement.

Engine-start droop is the hard case

A slow ramp from deep undervoltage exercises hold-up behaviour that a step transient never reaches.

Depot sustainment outlives the instrument

Programmes running 20+ years should confirm calibration and support horizons before standardising a rack.

Other standards this DUT usually faces

Further reading on MIL-STD-461G CS101

Send us the clauses you have to satisfy

We will come back with the source and load capability that covers them — and tell you plainly if something in your spec needs hardware we would not supply.

Talk to an engineer