Measurement library

AC power quality and UPS DC monitoring, with how each value is measured.

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99 of 99 measurements

99 measurements across 15 disciplines

Measured, derived, status and configured values

Measurement	ID	Type	Unit	Instrument	Definition	Cadence
Pole-to-pole DC voltageVoltage	V01	Measured	V DC	Isolated DC voltage input	Mean voltage between positive and negative conductors at each main bus and feeder. The nominal system value is 800 V pole-to-pole.	1 s aggregate; 2 s display
Positive pole to PEVoltage	V02	Measured	V DC	High-impedance isolated voltage input	Signed positive-conductor potential relative to protective earth. On a floating IT system this may drift; it is not a regulated +400 V rail.	1 s aggregate; 2 s display
Negative pole to PEVoltage	V03	Measured	V DC	High-impedance isolated voltage input	Signed negative-conductor potential relative to protective earth. Together with positive-to-PE voltage, reveals displacement of the floating system.	1 s aggregate; 2 s display
Voltage minimum and maximumVoltage	V04	Measured	V DC · time	DC meter extrema registers	Lowest and highest pole-to-pole voltage in the selected period, with timestamps and the meter aggregation interval. Separate from waveform event extrema.	1 s extrema; retained history
Distribution voltage dropVoltage	V05	Derived	V · %	Synchronized upstream/downstream meters	Upstream voltage minus feeder-end voltage; percent drop uses upstream voltage. Compare time-aligned readings under stable load and account for meter uncertainty.	1 s calculation
Pole-to-earth displacementVoltage	V06	Derived	V DC	Signed pole-to-PE voltage inputs	Common-mode potential = (Vpositive-to-PE + Vnegative-to-PE) / 2. Diagnostic only; a balanced value does not prove healthy insulation.	1 s calculation
Signed main-bus currentCurrent	I01	Measured	A DC	DC-rated Hall, zero-flux or isolated shunt sensor	Current through each independent bus. Positive denotes source-to-load flow; negative denotes reverse flow. Do not sum outgoing and returning conductor magnitudes as load current.	1 s aggregate; 2 s display
Signed feeder currentCurrent	I02	Measured	A DC	DC sensor at every monitored tap-off	Branch current for each rack or zone. Retain the circuit rating and polarity convention alongside the measurement.	1 s aggregate; 2 s display
Parallel conductor currentCurrent	I03	Measured	A DC	Individual DC sensors on parallel conductors	Current in each parallel positive or negative conductor where sensors are fitted. Supports identification of uneven sharing and overloaded individual paths.	1 s aggregate
Parallel conductor sharing errorCurrent	I04	Derived	%	Time-aligned parallel conductor current inputs	100 × maximum absolute deviation from the mean conductor current / absolute mean current, calculated for parallel conductors of the same pole. Suppress near zero load.	1 s calculation
Peak current and event timestampCurrent	I05	Measured	A · time	DC meter peak register / waveform recorder	Highest current with capture interval and timestamp. High-speed event peaks are distinct from peaks of slow display aggregates.	Event capture plus 1 s aggregate
Signed DC active powerPower & energy	P01	Measured	kW	Synchronized DC power meter	Mean of simultaneous instantaneous voltage × current samples. Positive is import to the load. Mean voltage × mean current is only a steady-state approximation when ripple correlation is negligible.	1 s meter aggregate
15-minute rolling demandPower & energy	P02	Derived	kW	Meter or historian	Average imported power over a rolling 15-minute window ending at each 5-minute sample boundary. The dashboard uses rolling demand rather than fixed demand blocks.	Recalculate at 5 min sample boundaries
Maximum 15-minute rolling demandPower & energy	P03	Derived	kW · time	Historian demand archive	Largest rolling 15-minute demand in the selected period, evaluated at 5-minute sample boundaries, with interval start and end timestamps. Independent per-path maxima must not be added.	Evaluate at 5 min sample boundaries
Imported energyPower & energy	P04	Measured	kWh	DC energy meter import register	Time integral of positive active power. Keep cumulative, interval and daily totals distinct, with reset/rollover handling.	1 min history; 2 s display
Exported energyPower & energy	P05	Measured	kWh	DC energy meter export register	Time integral of negative active power, reported as a positive exported-energy quantity. Do not hide reverse energy inside a net-only register.	1 min history; 2 s display
Bus and feeder utilizationPower & energy	P06	Derived	% · A spare	Current inputs plus approved operating limits	Absolute current divided by the applicable continuous operating limit. A configured nameplate rating is not automatically the allowable installed operating limit.	1 s calculation
Distribution loss and efficiencyPower & energy	P07	Derived	kW · %	Synchronized input/output DC power meters	Loss = input power minus summed downstream power, adjusted for storage and other branches. Efficiency = output/input. Flag results below combined meter uncertainty.	1 min average
AC-component voltage ripple RMSDC quality	Q01	Measured	V RMS	Isolated waveform analyzer	RMS of v(t) minus its DC mean. Always retain the measurement bandwidth, window and sample rate; example design band is 10 Hz–20 kHz.	1 s result; ≥100 kS/s acquisition
Voltage ripple peak-to-peakDC quality	Q02	Measured	V p-p	Isolated waveform analyzer	Maximum minus minimum AC-component voltage over the stated capture window and bandwidth. Not interchangeable with RMS ripple.	1 s result; ≥100 kS/s acquisition
Voltage ripple factorDC quality	Q03	Derived	%	Ripple RMS and DC voltage inputs	100 × AC-component voltage RMS / absolute DC mean voltage, using the same observation interval. State the bandwidth and suppress near zero DC voltage.	1 s calculation
AC-component current ripple RMSDC quality	Q04	Measured	A RMS · %	DC-capable current sensor plus waveform analyzer	RMS of current after removing its DC mean, with declared bandwidth. Relative ripple uses absolute mean current and is invalid near zero current.	1 s result; ≥100 kS/s acquisition
Sag, swell and interruption capturesDC quality	Q05	Measured	V · ms · count	Triggered voltage/current waveform recorder	Event type, threshold, start time, duration, minimum/maximum and pre/post-trigger waveform. Event duration comes from local fast acquisition, never inferred from 2-second dashboard polling.	Hardware-triggered event capture
Voltage slew rateDC quality	Q06	Derived	V/ms	Filtered high-speed voltage waveform	Maximum and minimum dV/dt over a specified event window. Derivative results must include sample interval and filtering to avoid presenting noise as a transient.	Triggered waveform calculation
Current slew rateDC quality	Q07	Derived	A/ms	Filtered high-speed current waveform	Maximum and minimum dI/dt with capture interval, sensor bandwidth and filter settings. Useful for dynamic load and fault-event diagnostics.	Triggered waveform calculation
Joint and conductor temperatureThermal	T01	Measured	°C	Installed contact sensors / calibrated IR system	Positive and negative bar joints, terminations and conductor temperatures with location identifiers. IR measurements require valid emissivity and line-of-sight assumptions.	5 s acquisition
Local ambient temperatureThermal	T02	Measured	°C	Ambient sensor near each monitored enclosure	Local air temperature paired with each thermal zone. Use it to distinguish high room temperature from local connection heating.	5 s acquisition
Temperature rise above ambientThermal	T03	Derived	°C rise	Joint and matching ambient sensors	Joint temperature minus local ambient temperature using aligned readings. Operating limits depend on the approved equipment, insulation and installation.	5 s calculation
Temperature rate of riseThermal	T04	Derived	°C/min	Temperature historian	Slope over a specified recent window, such as five minutes, with concurrent current/loading trend. A fast rise can matter before an absolute limit is reached.	1 min calculation
Connection voltage dropThermal	T05	Measured	mV	Isolated differential input across instrumented joint	Small differential voltage across a defined connection under load. Measurement must tolerate the bus common-mode voltage and use suitable isolation.	1 s aggregate
Estimated connection resistanceThermal	T06	Derived	µΩ	Joint mV drop and matching current sensor	R = 1000 × joint voltage drop in mV / current in A. Valid only at sufficient, stable current after offset compensation; this is an online estimate, not an offline micro-ohmmeter test.	1 min stable-load estimate
Estimated connection heating lossThermal	T07	Derived	W	Estimated joint resistance and RMS current	Approximate resistive loss = I RMS squared × R. With R in µΩ divide by 1,000,000. Distinguish this local estimate from metered whole-path losses.	1 min stable-load estimate
System insulation resistanceInsulation	G01	Measured	MΩ	Insulation monitoring device for floating IT DC	Effective resistance of the connected active system to PE. Trend each independent bus and retain response time, self-test status and lowest recorded value.	Native IMD update; display age explicitly
Pole-specific insulation estimateInsulation	G02	Derived	MΩ	Compatible IMD diagnostic registers, if available	Positive-to-PE and negative-to-PE estimates only if the selected IMD provides valid pole-specific data. Never infer an exact insulation resistance from pole voltage alone.	Native device update; otherwise N/A
System leakage capacitanceInsulation	G03	Measured	µF	Compatible IMD capacitance measurement	Connected system capacitance to PE. It affects insulation-monitor response and fault behavior; retain the IMD permitted capacitance and response characteristics.	Native IMD update
Residual / earth-leakage currentInsulation	G04	Measured	mA DC / RMS	DC-capable zero-flux residual sensor	Residual current around all active conductors, with bandwidth and DC/RMS basis stated. On a floating system this complements the IMD; it does not replace insulation-resistance monitoring.	1 s aggregate; local event detection
IMD health and connection statusInsulation	G05	Status	state · time	IMD self-test and connection monitoring	Device healthy/fault, test result and measuring-lead continuity. If buses are coupled, coordinate IMDs according to the approved architecture; do not assume independent monitors can operate on one connected system.	Device event; 2 s status poll
Located insulation faultInsulation	G06	Status	circuit · state	Compatible insulation-fault location system	Identified feeder, locator confidence/status and event time when a fault-locator is installed. Show Not instrumented if unavailable; residual current alone does not prove the location of an IT insulation fault.	Native locator scan / event
Breaker position and trip stateProtection	R01	Status	state	Independent breaker auxiliary/trip contacts	Closed, open, tripped or unknown for every main and branch device. Distinguish position feedback from commands and from current flowing through the circuit.	Event-driven; 2 s display
Trip cause and sequence of eventsProtection	R02	Status	cause · time	Protection relay / trip-unit event record	Latched cause, trip timestamp, operation sequence and captured fault data where supported. Preserve acknowledged versus cleared states and source timestamp quality.	Device event; source resolution retained
Protection and trip circuit healthProtection	R03	Status	state	Trip-unit diagnostics and supervision contacts	Trip-unit healthy, auxiliary supply healthy and trip-circuit continuity where supervised. No status may be labelled healthy when the channel is stale or absent.	Device event; 2 s status poll
DC device ratingsProtection	R04	Configured	V DC · A · kA	Approved manufacturer nameplate and coordination study	Rated DC voltage/current and applicable interrupting/withstand ratings, with required pole configuration and conditions. These are engineering metadata, not measured fault current or a live safety margin.	Engineering change control
Protection and alarm settingsProtection	R05	Configured	A · V · ms · °C · MΩ	Approved device settings / alarm configuration	Pickup, time delay, hysteresis, latching and reset rules, separately identifying hardware protection and dashboard alarms. Example dashboard thresholds are not approved equipment settings.	Engineering change control
Fuse, contactor, precharge and SPD healthProtection	R06	Status	state	Instrumented auxiliary contacts and controller registers	Show each fitted fuse alarm, contactor position, precharge ready/fault and surge protective device condition separately. Use Not instrumented for devices without feedback.	Event-driven; 2 s status poll
Arc detection statusProtection	R07	Status	state · time	Qualified DC arc detection system, if fitted	Detector health and alarm record only where an appropriate detector is installed. An absent alarm, normal bus telemetry or dashboard status cannot establish absence of arcing.	Detector event; otherwise Not instrumented
Rectifier module availabilitySources	S01	Status	online / total · state	Rectifier controller	Available, failed, standby and current-limited modules, including controller health. Available output capacity must reflect failed modules and operating derating.	Event-driven; 2 s poll
Rectifier current sharingSources	S02	Derived	A / module · %	Rectifier per-module DC current registers	Individual module output currents and maximum deviation from the mean among active modules. Evaluate at sufficient load and account for differing module ratings.	1 s aggregate
Rectifier conversion efficiencySources	S03	Derived	%	Synchronized AC input and DC output power meters	100 × DC output active power / AC input active power over the same interval. AC power quality belongs to the upstream meter view; it is not a DC bus measurement.	1 min average
Battery state of chargeSources	S04	Derived	%	Battery management system estimate	BMS-reported remaining charge fraction with data age and BMS estimation quality. State of charge is an estimate, not a direct guarantee of available runtime.	Native BMS update; 5 s display
Battery state of healthSources	S05	Derived	%	Battery management system estimate	BMS-reported health using the manufacturer definition and reference capacity. Track test date and estimator availability.	Native BMS update
Battery power and discharge limitSources	S06	Measured	kW · A	BMS / DC-DC converter and battery DC meter	Signed charge/discharge power and current, permitted discharge power/current, temperature derating and contactor readiness. Show polarity convention explicitly.	1 s aggregate; native limit update
Usable battery energy and runtimeSources	S07	Derived	kWh · min	BMS, approved reserve policy and load metering	Estimated runtime = bus-side usable energy / protected load × 60. Apply conversion efficiency only if energy is specified upstream of the converter. BMS discharge limits and actual contingency load still apply.	5 s estimate
Battery cell and temperature extremaSources	S08	Measured	V · mV · °C	BMS cell-level telemetry	Lowest/highest cell voltage, cell spread, hottest/coldest temperature and sensor location. Include BMS warning and fault states.	Native BMS update; 5 s display
Independent path availabilitySources	S09	Status	A/B state	Source, breaker and distribution status model	Availability of each complete source-to-load path, including module, breaker and dual-input load readiness. A closed main breaker alone does not prove redundancy.	Event-driven state evaluation
Post-contingency capacity and headroomSources	S10	Derived	MW · %	Approved topology, operating limits and actual load	Evaluate surviving source, bus, feeder and load-input limits after one path is lost. For two 800 V / 4000 A buses, nominal per-path power is 3.2 MW; 6.4 MW installed is not 6.4 MW redundant capacity.	1 s estimate; topology changes revalidated
Sample age and validityData quality	D01	Status	s · quality	Telemetry gateway and source timestamps	Good, stale, missing, out-of-range or substituted flags per measurement. Suppress derived healthy conclusions when any required input is invalid.	Every received sample
Time synchronization qualityData quality	D02	Measured	ms · state	PTP/NTP status and clock offset diagnostics	Clock source, offset and synchronization state for meters, gateways and event recorders. Unsynchronized readings cannot support precise event ordering or small loss calculations.	10 s health update
Calibration and measurement uncertaintyData quality	D03	Configured	date · % / absolute	Calibration records and complete measurement chain	Sensor/meter identification, range, accuracy, calibration date and due date. Include voltage-divider and current-sensor uncertainty when judging small changes or calculated losses.	Calibration / engineering record update
Acquisition and historian configurationData quality	D04	Configured	S/s · Hz · s	Meter and historian configuration	Acquisition sample rate, analog bandwidth, filters, averaging window, dashboard refresh and retention. These are distinct; slow polling cannot reconstruct fast electrical transients.	Configuration change control
Communications and sensor availabilityData quality	D05	Status	online / total · ms	Gateway diagnostics and expected-device inventory	Expected versus reporting channels, link latency, packet loss and gateway state. Coverage must be calculated against the configured inventory, not only devices that happen to report.	2 s status update
Phase-to-neutral RMS voltageAC voltage	AC-V01	Measured	V RMS	Three isolated AC voltage channels	Total true-RMS L1-N, L2-N and L3-N voltages for a configured three-phase four-wire wye system. Profiles use 480/√3 V at 60 Hz or 400/√3 V at 50 Hz; line-to-neutral values are not assumed identical.	Local cycle aggregates; 2 s display
Line-to-line RMS voltageAC voltage	AC-V02	Measured	V RMS	Synchronized phase-voltage channels	RMS of L1-L2, L2-L3 and L3-L1 differential waveforms, including modeled harmonics. Under unbalance, calculate each line voltage from its actual phase waveforms rather than multiplying an average by √3.	Local cycle aggregates; 2 s display
Frequency and extremaAC voltage	AC-V03	Measured	Hz · time	AC power-quality meter / PLL	Measured fundamental frequency with timestamped minimum and maximum over an explicitly defined interval. Frequency and 50/60 Hz belong to the AC-side measurement points, not the internal 800 VDC link.	Native meter frequency interval
Phase rotationAC voltage	AC-V04	Status	sequence	Three-phase voltage phasors	Positive sequence L1 → L2 → L3, reverse sequence or unknown. Keep phase labels and sensor polarity consistent through commissioning; a missing or invalid phase must invalidate the sequence conclusion.	Local phasor update
Negative-sequence voltage unbalanceAC voltage	AC-V05	Derived	%	Synchronized fundamental voltage phasors	100 × magnitude of negative-sequence voltage / magnitude of positive-sequence voltage. This differs from maximum RMS magnitude deviation from the three-phase mean; label both definitions separately.	Fundamental phasor interval
Neutral-to-PE voltageAC voltage	AC-V06	Measured	V RMS	Additional isolated voltage channel	Neutral-to-protective-earth potential at the monitored AC point, with connection and bandwidth stated. This requires its own measurement channel and is not inferred from phase-voltage unbalance.	If fitted: local RMS aggregate
Phase RMS currentAC current	AC-I01	Measured	A RMS	Three suitable CTs or isolated current sensors	Total true-RMS current per phase, including harmonic components. Current-sensor ratio, polarity, bandwidth, burden and saturation performance must match the application.	Local cycle aggregates; 2 s display
Neutral RMS currentAC current	AC-I02	Measured	A RMS	Neutral current sensor; synchronized phasor estimate optional	Neutral current includes phase unbalance and triplen harmonics. It can be measured directly or derived by summing the three instantaneous phase currents, and the display should say which.	Local cycle aggregates; 2 s display
Negative-sequence current unbalanceAC current	AC-I03	Derived	%	Synchronized fundamental current phasors	100 × negative-sequence current magnitude / positive-sequence current magnitude. Suppress ratios at insufficient current and distinguish sequence unbalance from simple phase-current magnitude spread.	Fundamental phasor interval
Voltage and current crest factorsAC current	AC-I04	Derived	ratio	Time-aligned waveform samples	Absolute waveform peak divided by total RMS over the same capture interval. A distorted waveform may exceed the sinusoidal √2 ratio. Current crest factor is undefined on the unloaded bypass.	Native waveform interval
Voltage/current phasorsAC current	AC-I05	Derived	V · A · degrees	Fundamental-frequency phasor estimator	Per-phase fundamental RMS magnitude and phase angle on a common reference. Current displacement from its own voltage establishes fundamental lead/lag; phasors do not depict total harmonic distortion.	Synchronized fundamental intervals
Residual / protective-earth currentAC current	AC-I06	Status	mA RMS · bandwidth	Dedicated residual-current sensor, if fitted	Residual current measured around all live conductors is separate from load neutral current. Converter loads require a sensor suited to the possible AC/DC components. Preserve sensor type and bandwidth.	If fitted
AC active powerAC power & energy	AC-P01	Measured	kW	Synchronized multiphase power meter	Mean instantaneous voltage × current per phase, summed for total power. Includes real harmonic power where both voltage and current harmonics exist. Positive denotes import from source toward the load.	Local waveform aggregate; 2 s display
Apparent powerAC power & energy	AC-P02	Derived	kVA	Synchronized RMS voltage/current meter	This dashboard defines total apparent power as the arithmetic sum of per-phase Vrms × Irms. Other effective-apparent-power conventions exist; preserve the meter definition when integrating real equipment.	Same interval as active power
Fundamental reactive power Q1AC power & energy	AC-P03	Derived	kvar	Fundamental voltage/current phasors	Sum of per-phase V1 × I1 × sin(displacement angle). Positive is lagging. Q1 excludes harmonic and distortion contributions; do not assume kVA² = kW² + Q1² under distorted conditions.	Fundamental phasor interval
True power factorAC power & energy	AC-P04	Derived	ratio	AC active and apparent power	True PF = active power / apparent power using the stated total-kVA convention. Includes waveform distortion effects and is undefined when the monitored bypass carries zero apparent power.	Same interval as power
Displacement power factorAC power & energy	AC-P05	Derived	ratio · lead/lag	Fundamental voltage/current phasors	Cosine of the fundamental voltage-current displacement angle per phase. Total DPF here is total fundamental active power / summed fundamental apparent power. It is distinct from true PF on nonlinear loads.	Fundamental phasor interval
AC imported and exported energyAC power & energy	AC-P06	Measured	kWh	Bidirectional AC energy registers	Accumulate positive and negative active energy separately; net energy is import minus export. Totals derived from other meters are not billing-grade registers.	Native registers; 1 min history
Rolling demand and peak demandAC power & energy	AC-P07	Derived	kW · time	Meter or synchronized historian	Rolling 15-minute average active power evaluated at 5-minute sample boundaries, plus its maximum over the stated history window. Per-path peaks are not added unless their demand intervals coincide.	5 min sample boundaries
Voltage THD-FAC harmonics	AC-H01	Derived	%	Harmonic analyzer with defined order range	100 × root-sum-square voltage RMS in harmonic orders 2–50 / fundamental voltage RMS, separately by phase. This excludes interharmonics and components above order 50; it is not a universal compliance verdict.	Specified harmonic analysis window
Current THD-FAC harmonics	AC-H02	Derived	%	Harmonic current analyzer and suitable sensors	100 × root-sum-square current RMS in orders 2–50 / fundamental current RMS. High THD at light load needs context. THD is undefined on the unloaded bypass and must not be substituted for TDD.	Specified harmonic analysis window
Individual voltage/current harmonicsAC harmonics	AC-H03	Measured	% fundamental · V · A	Synchronized voltage/current harmonic analyzer	Per-phase magnitude and phase for each harmonic order, with percent values referenced to that phase’s fundamental, across orders 2 through 50.	Native spectral window and grouping
Total demand distortion TDDAC harmonics	AC-H04	Derived	%	Harmonic current plus configured demand-current basis	100 × harmonic current RMS / maximum-demand fundamental current IL. Initially unavailable until a valid IL is configured. A configured IL, a snapshot value or an arbitrary current-THD threshold does not establish IEEE 519 compliance.	Harmonic interval; demand basis under change control
InterharmonicsAC harmonics	AC-H05	Status	V / A · Hz	Compatible interharmonic analyzer, if fitted	Components between integer harmonics require suitable spectral grouping, windowing and instrument capability. A zero placeholder must not imply that interharmonics are absent.	If fitted
Conducted components from 2–150 kHzAC harmonics	AC-H06	Status	V / A · kHz	Suitable wideband analyzer and probes, if fitted	High-frequency conducted components require defined bandwidth, grouping, transducers and measurement methods. An orders-2–50 spectrum does not establish coverage of the 2–150 kHz band.	If fitted
Voltage sagAC events & flicker	AC-Q01	Measured	% nominal · ms · phase	Locally triggered power-quality event recorder	Store residual RMS voltage, affected phases, start/end time, duration and threshold basis.	Local event detection and retained capture
Voltage swellAC events & flicker	AC-Q02	Measured	% nominal · ms · phase	Locally triggered power-quality event recorder	Store elevated RMS voltage, event duration, affected phases and synchronized waveform/envelope. Compare to the configured nominal system voltage and documented operational threshold.	Local event detection and retained capture
Voltage interruptionAC events & flicker	AC-Q03	Measured	% nominal · ms · location	Locally triggered voltage recorder	Record residual voltage, affected measurement point and duration. An interruption on an idle bypass source is distinct from loss of the inverter output or a load outage.	Local event detection and retained capture
Oscillatory / impulsive transientAC events & flicker	AC-Q04	Measured	V peak · µs / ms	Appropriate high-speed transient recorder	Instantaneous peak voltage, polarity, ringing frequency and duration from an adequately sampled capture. A transient peak is not an RMS residual percentage.	Hardware-triggered high-speed acquisition
Correlated input/output waveformsAC events & flicker	AC-Q05	Measured	V · A · ms	Time-synchronized upstream/downstream event recorders	Compare disturbance timing at the UPS input, bypass and inverter output. Retain mode, pre/post-trigger windows and clock uncertainty. A maintained output in one event does not prove equipment ride-through or transfer performance.	Local triggered buffers with synchronized clocks
Short-term flicker PstAC events & flicker	AC-Q06	Measured	index · 10 min	Compatible IEC flickermeter	Short-term flicker severity from a completed 10-minute instrument interval. Pst cannot be calculated from a short snapshot waveform or a simple voltage-RMS spread.	Completed 10 min intervals
Long-term flicker PltAC events & flicker	AC-Q07	Derived	index · 2 h	Twelve valid consecutive Pst values	Cube root of the mean of the cubes of 12 consecutive 10-minute Pst values. Retain all interval timestamps and validity.	Trailing 12 completed 10 min intervals
Rapid voltage changesAC events & flicker	AC-Q08	Status	% nominal · time	Compatible local RVC detector, if fitted	Identify rapid changes in RMS voltage using the adopted measurement method, thresholds, hysteresis and event flags. Sag/swell examples do not by themselves provide RVC coverage.	If fitted
UPS mode and source stateAC system & data	AC-S01	Status	state · time	UPS controller and independent position feedback	Normal double conversion, static bypass, battery operation or maintenance state from the installed system. Read-only: the monitoring system provides no switching commands.	Event-driven controller status
Conversion-boundary power and lossAC system & data	AC-S02	Derived	kW · %	Synchronized AC/DC meters at matching boundaries	Rectifier AC input, 800 VDC link, DC-fed inverter sections, inverter AC output and downstream PDU output. Calculate losses using aligned meters; do not count the same energy at successive boundaries as separate facility load.	Aligned 1 min averages
AC ratings and protection metadataAC system & data	AC-S03	Configured	V · A · kA · curve	Approved device nameplates and coordination study	Continuous limits, CT/PT ratios, short-circuit interrupting/withstand ratings and protection settings. Prospective fault current cannot be inferred from normal operating current.	Engineering change control
AC meter quality and commissioning stateAC system & data	AC-S04	Status	quality · time · date	Meter, gateway and commissioning records	Source timestamp, freshness, missing channels, synchronization, calibration, polarity and instrument-class evidence. A mathematically valid snapshot does not establish real meter availability or calibration.	Every received sample and status change
PCC and assessment basisAC system & data	AC-S05	Configured	configuration · evidence	Approved connection study and measurement plan	Identify the actual point of common coupling, demand-current IL basis, fault-level basis and applicable measurement duration/statistics. Operational thresholds provide advisories only; no IEEE 519 or IEC compliance pass is implied.	Engineering assessment; not an instantaneous reading
Bypass synchronization and transfer permissiveAC system & data	AC-S06	Status	V · Hz · degrees · state	UPS controller and synchronized source/output measurements	Retain voltage, frequency and phase-angle differences plus manufacturer-reported transfer permitted/inhibited. An energized bypass alone does not prove availability for a safe transfer.	Controller status and native synchronism intervals

99 matching definitions · Three-phase AC distribution + 800 VDC UPS link · Independent A/B

Which measurements apply depends on the sensors fitted at a given site. Cadences are design targets.

Technical references

Standards and primary technical references behind the measurement design

NVIDIA · 800 VDC data-center architecture Architecture context for the illustrative 800 V pole-to-pole system; not a site-specific electrical design.
Bender · ISOMETER iso685 Insulation monitoring, system capacitance, connection monitoring and self-test for unearthed AC/DC systems.
Bender · Residual-current measurement principles Explains DC-sensitive residual monitoring. Grounded-system RCM guidance does not replace an IMD on this floating IT example.
Yokogawa · WT5000 power measurement Reference for synchronized voltage, current and power acquisition, DC accuracy and waveform bandwidth; no specific installed instrument is implied.
IEC 61000-4-30:2025 · PQ measurement methods The current IEC measurement-method framework. Method classes and documented instrument evidence are separate from operating acceptance limits.
IEEE 519-2022 · Harmonic control at the PCC Steady-state harmonic assessment applies at the identified point of common coupling. A spot THD reading does not establish compliance.
HIOKI · AC measurement equations Primary definitions for RMS, power, fundamental components, reactive power and unbalance. Meter calculation conventions must be retained.
Schneider Electric · THD and TDD Distinguishes harmonic distortion denominators and the maximum-demand current used for TDD.
HIOKI · Flicker measurement settings Instrument settings for Pst observation intervals and the number of Pst intervals used for Plt.

The design uses configurable three-phase AC profiles and an assumed 800 V two-wire floating UPS DC link. Voltage class, grounding, ratings, sensor selection and operating limits are mapped to the actual installation. References inform the design: they do not certify this demonstration, and listing one does not imply a partnership or an endorsement.