With real, field-style examples (and how SnapCor/TICOR reporting keeps it consistent)
When you hand an IR report to a facilities manager, a data centre ops lead, or an insurer’s risk engineer, they usually don’t ask, “What was the emissivity?” They ask one thing:
“How bad is it… and what do we do next?”
That’s why hotspot grading matters.
In the real world, “hotspot grade” is shorthand for risk + urgency + clarity. It turns thermography from “interesting images” into actionable maintenance—and it helps teams standardise decisions across different engineers, sites, and clients.
SnapCor was built to make that grading fast and consistent: works with any thermal camera, produces instant on-site reporting, and is powered by a field-tested TICOR engine.
This guide breaks down what Grades 1, 2, and 3 mean in electrical thermography, what inspectors should record, and how SnapCor/TICOR-style reporting keeps the output clean, defensible, and repeatable.
First: what exactly is a “hotspot grade”?
A hotspot grade is not just a temperature number.
A proper grade typically considers:
- ΔT (temperature rise) vs a reference or similar component
- Load at the time of inspection (and whether the component is likely to run hotter at peak load)
- Component type & criticality (UPS, busbar joints, LV switchgear incomers, PDUs, etc.)
- Pattern of heating (connection resistance vs overload/imbalance)
- Environment (cubicle ambient, ventilation, cover-on limitations, reflective surfaces)
Many formal guidance documents and programmes treat severity criteria as program-specific and built from experience and accumulated data.
And that’s where a structured reporting engine helps: it forces the same logic every time.
Why Grades 1–3 are useful (especially for FM + multi-engineer teams)
When multiple engineers are inspecting multiple buildings, the common failures aren’t always the scanning—they’re the reporting:
- One engineer calls it “urgent”, another calls it “monitor”
- One report is detailed, another is vague
- The recommendation is inconsistent
- Next year’s inspector can’t trend it properly
A simple 3-grade system is popular because it’s easy for clients to action:
- Grade 1 = Monitor / plan
- Grade 2 = Schedule repair (soon)
- Grade 3 = Urgent / immediate risk
SnapCor supports that “inspection-led workflow” approach—capture, log ΔT/load/severity and generate a PDF report before leaving site.
How SnapCor/TICOR grades faults (the practical mechanics)
TICOR’s electrical module is built for on-site electrical reporting using structured drop-downs (so the report is written during inspection, not after).
The big differentiator: load correction + automatic grading
A key problem in electrical thermography is false confidence when the load is low.
TICOR’s electrical module includes integrated load correction formulae, allowing faults to still show as critical even when measured temperature is close to ambient—because it estimates component behaviour at maximum load and then grades severity automatically.
A real TICOR-style sample report explains it clearly:
- It estimates fault component temperature at full load
- Then uses a fault rating system (Minor/Important/Serious/Critical)
- With threshold bands based on 100% load corrected temperature.
That’s exactly the kind of “consistent engine” SnapCor builds on for modern teams.
Mapping TICOR’s severity to Grades 1–3 (simple, client-friendly)
Some engines use 4 levels (Minor/Important/Serious/Critical). But many FM teams prefer 3 action grades.
Here’s a clean mapping you can use in your reporting language:
✅ Grade 1 (Monitor / Plan)
Typically aligns with: Minor (and sometimes low “Important”) Meaning: early indicator, low immediate risk, fix when practical.
✅ Grade 2 (Repair Soon / Scheduled)
Typically aligns with: Important → Serious Meaning: credible defect, increasing risk, plan remedial work in a defined timeframe.
✅ Grade 3 (Urgent / Immediate)
Typically aligns with: Critical (and high “Serious”) Meaning: high risk of failure, significant heat rise, possible fire/flashover/downtime risk—action ASAP.
Note: Severity tables vary. For example, one widely used guideline shows that ΔT from reference of 1–10°C may be “possible deficiency—monitor”, 21–40°C “repair at next opportunity”, and >40°C “repair immediately.” That’s why standardising your method matters more than chasing one universal number.
Grade-by-Grade: what to capture, what to write, and how to make it defensible
Grade 1 — “Monitor & maintain”
What it often looks like
- Small ΔT vs reference
- Early stage connection resistance OR mild imbalance/overload that needs context
- No visible damage
What to capture in the report
- ΔT vs reference/similar phase (not just absolute temp)
- Load reading (even an approximate % is better than nothing)
- Clear asset ID + location
- One thermal + one visual image for context
What the recommendation should say
- “Monitor and recheck next cycle” is not enough by itself Add: “inspect/torque during next planned shutdown” or “compare phases / verify loading”
Why SnapCor/TICOR helps here
- Drop-down libraries + common sentences reduce vague wording and keep Grade 1 language consistent across engineers.
Grade 2 — “Schedule repair soon”
What it often looks like
- Moderate ΔT vs reference
- Repeat fault from last inspection (trend worsening)
- Fault pattern consistent with high resistance connection
Remember: in many programmes, the majority of electrical IR problems are high resistance points of contact, not overload.
What to capture in the report
- ΔT vs a like-for-like component
- Load and any known operational context (UPS on battery test? generator running? peak HVAC load?)
- If possible: compare phases and note whether imbalance is expected
What the recommendation should say
- Clear timeframe language the client can act on: “Repair at next opportunity / within X days” (aligned to your client’s maintenance policy)
Why SnapCor/TICOR helps here
- Load correction and integrated formulas support more reliable severity when equipment isn’t at full load.
- Structured fields make “Grade 2” consistently mean the same thing across sites.
Grade 3 — “Urgent / immediate risk”
What it often looks like
- High ΔT or very high corrected full-load estimate
- Severe heating at lugs, joints, busbar connections, UPS/battery links, incomers
- Potential damage to insulation, risk of failure/downtime
What to capture in the report
- Thermal + visual image (showing exactly which component)
- Clear severity statement (don’t hide it in paragraphs)
- The likely root cause + immediate action
What the recommendation should say
- “Investigate immediately” plus a practical instruction: isolate, torque-check, replace, clean/retighten, check for corrosion, verify conductor sizing, review loading, confirm protective device settings (only what you can reasonably support)
Why SnapCor/TICOR helps here
- Automatic grading up to critical severity and on-site report generation supports faster escalation while you’re still on the client’s premises.
Real Examples (written like a SnapCor/TICOR fault page)
These are illustrative examples (the point is structure + clarity). Your exact thresholds should follow your programme criteria.
Example 1 — Grade 1: mild heating on an MCB lug (monitor/plan)
- Asset: LV Panel LP-2 → Circuit 12
- Observed: small ΔT vs similar circuits
- Load: moderate
- Grade: 1
- Likely cause: early-stage connection resistance or minor load variation
- Action: recheck next cycle and torque inspect during planned shutdown
Example 2 — Grade 2: one phase on a distribution board running hotter than similar phase
- Asset: DB-1 → Phase L2
- Observed: clear ΔT vs like-for-like phase component
- Load: high and stable
- Grade: 2
- Likely cause: high resistance point (common in electrical IR findings)
- Action: schedule remedial work soon; verify torque/termination condition; retest after repair
Example 3 — Grade 3: busbar joint hotspot (urgent)
- Asset: Busbar run → joint J-14
- Observed: strong hotspot at joint vs adjacent joints
- Load: unknown at time, but correction used (where applicable)
- Grade: 3
- Likely cause: joint degradation / contact resistance
- Action: urgent isolation/repair plan; confirm mechanical integrity and retest
SnapCor specifically calls out busbar workflows and trending to prove coverage and track joints over time—useful for high-density environments.
The “don’t get caught out” section: grading mistakes inspectors make
1) Using absolute temperature only
Many programmes explicitly say differential analysis is more reliable than absolute temperature because it’s less affected by environmental factors.
2) Ignoring load (or guessing it)
Load drives heat. A good grading workflow either captures load properly or uses a structured method to interpret low-load readings.
3) Writing “repair immediately” with no technical justification
If you escalate, show your evidence: ΔT, reference, asset criticality, fault pattern.
4) Inconsistent language between engineers
This is where knowledge-based libraries and standard sentences matter—TICOR explicitly describes that approach.
Why SnapCor makes grading easier for mixed teams (FM, contractors, enterprise)
If you’re managing reports across multiple engineers, the goal isn’t “more detail”—it’s repeatable decision-making.
SnapCor is designed to standardise the workflow:
- Works with any thermal camera.
- Inspection-led reporting that matches how engineers work on site.
- Consistent severity grading via the TICOR electrical module (Minor/Important/Serious/Critical)
- Drop-down libraries for fault types and remedial actions
- One-tap PDF generation before leaving site.
That’s exactly what “Grades 1–3” need to be valuable: consistent inputs → consistent output.
Quick FAQ
What’s the difference between hotspot Grade 2 and Grade 3? Grade 2 is a credible defect you can schedule. Grade 3 is an escalation: high risk, high urgency, or high criticality.
Is ΔT more important than absolute temperature? Usually, yes. Differential analysis is often treated as more reliable in practice.
What causes most electrical hotspots? High resistance points at connections are commonly reported as the majority of electrical thermography findings.
Do severity thresholds differ by programme? Yes—many guidelines explicitly say severity criteria should be tailored to your operation and equipment.
How do you grade when load is low? A structured approach helps—TICOR’s electrical module describes integrated load correction to estimate max-load behaviour and grade faults.
Can SnapCor standardise grading across a team? That’s one of its core use-cases—consistent severity grading, structured reporting, and standardised outputs.
