Technical manual · simulated electrical power monitoring
EPMS Telemetry Dashboard
This manual explains the one-line topology, state machine, electrical calculations, telemetry labels and report actions behind EPMS_Telemetry.html. Values are browser-simulated unless explicitly bound to CONV_CALC.snapshot.
01 Purpose & engineering basis
The cockpit is an educational EPMS one-line for exploring electrical reachability and source-transfer behavior. Its shared site KPIs use the Conventional DC locked model; its wire and bottom-bar values remain an illustrative simulator layer.
| Basis item | Value | Unit | Authority |
|---|---|---|---|
| Current IT load | 1,850 | kW | CONV_MODEL.site.it_load_kw. |
| Power usage effectiveness | 1.45 | ratio | CONV_MODEL.site.pue. |
| Facility load | 2,682.5 | kW | CONV_CALC.facilityLoadKw(). |
| Non-IT load | 832.5 | kW | CONV_CALC.nonItLoadKw(). |
| UPS efficiency | 0.96 | ratio | Conventional engineering basis doc 09. |
| EPMS aggregate tolerance | ±2 | % | Conventional QA acceptance doc 12. |
| Utility / MV level | 20,000 | V line-to-line | WIRES[].v. |
| LV distribution | 400 | V line-to-line | WIRES[].v. |
| Rack branch label | 230 | V | WIRES[].v; phase interpretation remains unresolved. |
| Current-calculation PF | 0.90 | ratio | Local calcPowerFlow() constant. |
Data-mode rule: the top Facility/IT/PUE values are deterministic engine outputs. The bottom Total Load, PF and Frequency are jittered demonstrations, and the wire kW values are destination-class assignments. Do not treat the latter as calibrated meters.
02 Topology & interface map
The page uses a three-stream topology. Streams A and B have direct utility incomers; stream C is a catcher path reached through the MV ring. Equipment is generated from DEVICES and connections from WIRES.
| Layer | Tags / controls | Meaning | Operator action |
|---|---|---|---|
| Header | Back, Portfolio, PRD, Manual | Navigation only. | Open related public documentation without changing simulation state. |
| View controls | 50%, 75%, 120%, Fit, Reset View | Transform #scene. | Use Fit after resize; drag the canvas to pan; wheel to zoom. |
| Report controls | PDF, CSV, JSON | Snapshot of local simulator state. | Allow popups/downloads; verify the report timestamp and simulation scope. |
| Source controls | Utility A, Utility B, MV Bus Coupler | Source availability and tie position. | Select only as a training input; watch ATS/log response. |
| Generator indicators | GEN A/B/C | ATS-commanded running state. | Read only; these are not manual start buttons. |
| MV | MV_A/B, RMU_A/B/C, TX_A/B/C | 20 kV incoming, ring and transformation. | Select associated breaker symbol to exercise state. |
| LV / distribution | LVSB_*, ATSDB_IT_*, ATSDB_M_*, ATS_PNL1/2 | 400 V boards and catcher ties. | Trace energized line and breaker state. |
| Protected IT | UPS_A/B/C, PDU_*, rATS_0…9, RACK_0…9 | UPS-to-representative-rack distribution. | Do not interpret ten racks as the full site. |
| Mechanical | UPS-M A/B, CH-1…4, AHU-1/2, DAHU A/B 1…5 | Critical cooling support loads. | Inspect path and telemetry label. |
| Breaker gesture | Click / Alt-click / Shift-click | Toggle / force open / trip. | Use only in simulation; trip increments alarms. |
| Status | System, Total Load, PF, Frequency, Breakers, Alarms, clock | Bottom roll-up. | Reconcile only state counts; recognize jittered measurements. |
03 Inputs, point classes & state
There are three input classes: engine basis, user-driven simulator state and browser-generated display jitter. Keeping these classes separate prevents a simulated label from being mistaken for a meter.
| Class | Input / state | Consumers | Quality rule |
|---|---|---|---|
| Locked engineering basis | CONV_CALC.snapshot.site | Top Facility, IT and PUE strip. | Deterministic; missing engine must become unavailable, not silently GOOD. |
| Source state | SIM.sources.A/B | Source buttons, ATS logic, flow reachability, System mode. | Local simulated state. |
| Generator state | SIM.genRunning.A/B/C | Generator indicators and generator-fed path. | Local ATS outcome. |
| Breaker state | SIM.breakers[br_*] | Symbols, flow, breaker/alarm counts, exports. | Local simulated state; enum must be closed/open/trip. |
| Reachability | SIM.energizedNodes | Animated flow and downstream recursion guard. | Derived every 500 ms; not persisted. |
| Wire configuration | WIRES | Topology, nominal voltage, breaker tag, default state. | Static source code. |
| Equipment configuration | DEVICES | Tags, location, type and nameplate text. | Static source code. |
| Display jitter | Math.random() | Total Load, PF, Frequency. | Illustrative/estimated; must never be exported as metered without a provenance field. |
| Browser clock | Date | Bottom timestamp and report timestamp. | Display time only; not acquisition time. |
04 Calculation methodology
Facility balance
P_facility = P_IT × PUEP_facility = 1,850 kW × 1.45 = 2,682.5 kWTop strip display: 2.68 MW facility · 1.85 MW IT · PUE 1.45Source:
CONV_CALC.snapshot.site; conventional review doc 09.Three-phase current
P_3φ = √3 × V_LL × I × PF / 1,000I = P_kW × 1,000 / (√3 × V_LL × PF)Symbols:
P_kW active power, V_LL line-to-line voltage, I line current, PF power factor. The simulator uses PF 0.90 and applies floor().Single-phase branch boundary
P_1φ = V_LN × I × PF / 1,000I_1φ = P_kW × 1,000 / (V_LN × PF)The current cockpit does not branch on phase type; its 230 V rack labels still use the three-phase expression. This formula is the required correction if those branches are truly single phase.
State roll-ups
closed = Σ [breaker.state = "closed"]alarms = Σ [breaker.state = "trip"]system = (utilityA ∨ utilityB) ? "ONLINE" : "GEN MODE"Source:
updateStatusBar(). An open breaker is not counted as an alarm in the current implementation.Illustrative meter jitter
P_display = 2,400 + floor(U[0,1) × 100) kWPF_display = round(0.92 + U[0,1) × 0.03, 2)f_display = round(50.0 + (U[0,1) − 0.5) × 0.1, 1) HzThese are display ranges, not sourced facility equations. They intentionally remain labeled as a limitation.
05 ATS, breaker & power-flow state machine
The state machine is reachability-based, not an AC load-flow solver. It evaluates source health, manipulates utility/generator incomer breakers and recursively marks downstream nodes energized through closed breakers.
| State / transition | Condition | Action | Visible result |
|---|---|---|---|
| A utility healthy | Utility A direct, or Utility B through closed MV tie. | Generator A incomer opens; after 1 s utility A incomer closes and generator stops. | A path energized from utility; GEN A standby. |
| B utility healthy | Utility B direct, or Utility A through closed MV tie. | Generator B incomer opens; after 1 s utility B incomer closes and generator stops. | B path energized from utility; GEN B standby. |
| C utility healthy | Reachable A ring or B ring through its breaker chain. | Generator C transfer follows the same restore/loss sequence. | C catcher path energized by the reachable ring source. |
| Utility lost | Stream health false while utility incomer is closed. | Open utility incomer, mark generator running, then close generator breaker after 2 s. | Log entries, generator indicator and generator-styled flow. |
| Manual breaker toggle | Click a breaker group. | closed ↔ open. | Symbol class and downstream reachability update. |
| Manual trip | Shift-click a breaker group. | Set state to trip. | Trip X, fault-red state and alarm count. |
| Manual open | Alt-click a breaker group. | Set state to open. | Open symbol and downstream de-energization. |
| Power-flow refresh | 500 ms interval. | Clear flows/labels, traverse from available sources through closed breakers. | Current reachable paths animate; all others read zero. |
Safety boundary: this sequence omits synchronism check, voltage/frequency permissives, dead-bus logic, protection coordination, breaker travel time, lockout, retry limits and operator confirmation. It must never be copied into field control code.
06 Worked example
The example separates the shared site aggregate from one wire-label calculation and from the representative rack row.
- Facility aggregate:
1,850 × 1.45= 2,682.5 kW. - Top-strip rounding:
2,682.5 / 1,000to two decimals = 2.68 MW. - Example MV wire: assigned
P=2,400 kW,V_LL=20,000 V,PF=0.90. - Calculated current:
2,400,000 / (1.732 × 20,000 × 0.90)= 76.98 A; the cockpit floors this to 76 A. - Representative rack row: ten branches × 6 kW = 60 kW.
- Scope gap:
1,850 − 60= 1,790 kW not represented by the ten rack symbols. - Interpretation: the diagram must be read as a representative protected row unless a future model allocates the entire site load across aggregate PDU groups.
The bottom bar may simultaneously show a random 2.4–2.499 MW total. That is not a second facility-balance calculation; it is an unresolved simulator display and should not be used to validate PUE.
07 Telemetry quality, alarms & exports
| Surface | What it currently means | What it does not prove | Required operator reading |
|---|---|---|---|
| Data GOOD | Static page declaration. | No acquisition health, stale-age or per-point quality check. | Read together with Scenario Simulated. |
| Timestamp | Browser clock refreshed each second. | Not a meter sample time. | Use as UI time only. |
| Alarm count | Count of breaker states equal to trip. | No ISA-18.2 lifecycle, acknowledgement, shelving or priority. | Use to locate simulated trips in the one-line. |
| Open breaker | User/ATS state that interrupts reachability. | Not automatically abnormal. | Interpret with expected topology and log. |
| PDF report | Printable HTML with summary and source/generator states. | Not a signed commissioning record. | Confirm timestamp and current state before printing. |
| CSV | Metrics, sources, generators and every breaker state. | No schema version, units column for all rows or quality flag. | Treat as local simulator export. |
| JSON | Timestamp plus source/generator/breaker state and summary strings. | No persistent historian identity. | Use for teaching/test fixtures only. |
08 Standards mapping
| Standard / source | Relevant subject | Current implementation status |
|---|---|---|
| IEC 60364 | Low-voltage electrical installations. | Context only; conductor sizing and protection are not calculated. |
| IEC 60909 | Short-circuit currents. | Not implemented; no fault-level output should be inferred. |
| IEC 61850 | Substation object models and communications. | Not implemented; point IDs are local DOM/model names. |
| IEC 60870-5-104 | Telecontrol exchange. | Not implemented. |
| IEEE C37.2 | Protection/control device-function numbers. | Recommended for a future breaker inspector. |
| IEEE 1584 / NFPA 70E | Arc-flash calculation and electrical safe work. | Explicitly outside simulator scope. |
| ISO/IEC 30134-2 | PUE definition. | Shared Conventional model provides PUE 1.45; EPMS page does not independently calculate it. |
| Conventional review docs 00/02/09/12 | Single site basis, EPMS gaps, formulas and acceptance. | Primary internal engineering review source. |
09 Glossary & RZExplain
Terms below are marked for the shared RZExplain scanner so a reader can inspect definitions without leaving the manual.
| Term | Meaning in this cockpit |
|---|---|
| EPMS | Electrical Power Monitoring System; the cockpit models display and state, not a field acquisition server. |
| ATS | Automatic Transfer Switch or transfer function between normal and alternate source. |
| RMU | Ring Main Unit in the 20 kV distribution path. |
| LVSB | Low-Voltage Switchboard downstream of a transformer. |
| UPS | Uninterruptible Power Supply protecting IT or critical mechanical load. |
| PDU | Power Distribution Unit between UPS/catcher feed and rack ATS. |
| Power factor | Active power divided by apparent power; the wire calculation assumes 0.90. |
| PUE | Facility energy divided by IT energy; the shared scenario is 1.45. |
| Open / trip | Open is a position; trip is a simulated fault state counted as an alarm. |
| Representative row | The ten 6 kW rack symbols, which do not represent the full site IT load. |
10 Limitations & validation checklist
Use the cockpit only inside its declared simulation boundary. The following checks are mandatory before accepting a future revision.
| Check | Expected result | Known present limitation |
|---|---|---|
| Facility balance | EPMS aggregate within ±2% of 2,682.5 kW. | Bottom Total Load is 2.4–2.499 MW jitter and does not reconcile. |
| IT roll-up | Sum of protected IT outputs equals 1,850 kW or scope is labeled. | Ten racks total only 60 kW. |
| Phase/current model | Formula matches branch phase and voltage definition. | 230 V branch uses three-phase formula. |
| Data quality | Every point has source, sample timestamp, quality and stale threshold. | Only a static GOOD label exists. |
| Alarm lifecycle | Severity, timestamp, cause, acknowledgement and clear state. | Only trip count exists. |
| Transfer safety | Permissives, timeouts, interlocks and failure states are explicit. | Browser timers implement a simplified success path. |
| Color semantics | Red reserved for fault/trip. | Normal source A flow is red. |
| Accessibility | All source/breaker controls work from keyboard with state announcement. | Several controls are divs and breaker state uses pointer modifiers. |
| Responsive behavior | No page overflow at 360 px; key controls reachable. | Diagram remains a desktop-scale engineering canvas. |