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Panel heat calculator

Add up what the devices in a board give off, and check it against what the enclosure can shed — modules and watts, both budgets at once.

Updated August 2026

The enclosure Pick one or two boards. The permissible dissipation and the module count come from the enclosure data.

Board 1

Board 2 — optional

Boards built together

Adjacent boards warm each other, so the permissible dissipation is reduced by 10 %. The source for the 10 % has not been established.

Margins Three numbers decide how much of the board you are allowed to use. Each is easy to enter wrongly.

Between 0 and 1. Not everything draws current at once. 0 means no reduction and is treated as 1.0.

Between 0 and 0.9 — the fraction held back. 0.2 keeps 20 % free for later additions, in both budgets.

Between 0 and 0.5. Heat in the internal wiring, as a fraction. 0.1 adds 10 % — not 10.

Protective devices Everything on the DIN rail that is not a smart device. Quantity defaults to 1 and is always shown.
Smart devices Shelly Pro, and at the bottom of the list the discontinued IHC range.

Result Both budgets have to balance. A board can be thermally fine and still physically full.

Module budget

Available
—
Consumed
—
Remaining
—
Load
—

Thermal budget

Allowed
—
Dissipated
—
Remaining
—
Load
—

Pick an enclosure to see a result.

Show calculation
What this tool is, and is not

It is a design aid for choosing an enclosure. It is not a verification to any standard, and it does not replace the enclosure manufacturer's documentation or the panel builder's responsibility for the finished board.

Ambient temperature is not accounted for. An enclosure's permissible dissipation falls as the room around it gets warmer, so a board in a warm utility room has less headroom than this calculation shows.

Where a figure is not published by the manufacturer, the result is an estimate.

Original tool by vocational teacher Kim Mathiesen · revised 2026

The figures behind the calculation

Every enclosure and every device the picker offers, with the data-quality tier beside it. Nothing here is needed to use the tool — it is here so a single number can be checked without building a calculation around it.

Enclosures
NamePermissible dissipationModules
UG 213 W2
UG 625 W6
UG 1230 W12
UG 1835 W18
UG 2440 W24
PGE 150-722 W7
PGE 150-1428 W14
PGE 150-2132 W21
PGSE 150-1837 W18
Resi9 CX 1x1327 W6.5
Resi9 CX 2x1335 W13
Resi9 CX 3x1355 W19.5
Resi9 CX 4x1361 W26
Resi9 CX 1x1835 W9
Resi9 CX 2x1848 W18
Resi9 CX 3x1870 W27
Resi9 CX 4x1890 W36

The permissible dissipation and the reference temperature of the enclosures have not been sourced yet, and neither has the 10 % reduction for boards built together.

Protective devices
NameDissipationModulesData quality
Surge protection device, 2-pole0 W1assumed 0 W
Surge protection device, 4-pole0 W2assumed 0 W
Resi9 2p RCD 40A7.2 W1legacy table
Resi9 4p RCD 40A14.4 W2legacy table
Resi9 4p RCD 63A14.4 W2legacy table
Resi9 XP RCBO 1PN C10A 6kA 30mA kl. A2.3 W1legacy table
Resi9 XP RCBO 1PN C13A 6kA 30mA kl. A2.8 W1legacy table
Resi9 XP RCBO 1PN C16A 6kA 30mA kl. A3.1 W1legacy table
Resi9 XP RCBO 3PN C10A 6kA 30mA kl. A6.3 W2legacy table
Resi9 XP RCBO 3PN C16A 6kA 30mA kl. A5.7 W2legacy table
Resi9 XP RCBO 3PN C20A 6kA 30mA kl. A9.3 W2legacy table
Group switch 1P+N2.5 W1legacy table
Group switch 3P+N7.5 W2legacy table
Group switch 3P+N 63 A16.5 W2legacy table
Resi9 XP MCB 1PN C6A 6kA 18mm1.4 W0.5legacy table
Resi9 XP MCB 1PN C10A 6kA 18mm2.2 W0.5legacy table
Resi9 XP MCB 1PN C13A 6kA 18mm3.3 W0.5legacy table
Resi9 XP MCB 1PN C16A 6kA 18mm3.5 W0.5legacy table
Resi9 XP MCB 1PN C20A 6kA 18mm4.2 W0.5legacy table
Resi9 XP MCB 3PN C10A 6kA 54mm6.3 W1.5legacy table
Resi9 XP MCB 3PN C13A 6kA 54mm8.4 W1.5legacy table
Resi9 XP MCB 3PN C16A 6kA 54mm9.3 W1.5legacy table
Resi9 XP MCB 3PN C20A 6kA 54mm9.3 W1.5legacy table
Resi9 XP MCB 3PN C25A 6kA 54mm10.2 W1.5legacy table
Resi9 XP MCB 3PN C32A 6kA 54mm10.2 W1.5legacy table
Tytan I 1P+N 6 A1.1 W1legacy table
Tytan I 1P+N 10 A1.7 W1legacy table
Tytan I 1P+N 13 A2.6 W1legacy table
Tytan I 1P+N 16 A2.6 W1legacy table
Tytan I 3P+N 6 A3.4 W2legacy table
Tytan I 3P+N 10 A5.2 W2legacy table
Tytan I 3P+N 13 A7.5 W2legacy table
Tytan I 3P+N 16 A7.5 W2legacy table
Tytan II 1P+N 25 A3.02 W1.5legacy table
Tytan II 1P+N 35 A4.56 W1.5legacy table
Tytan II 1P+N 50 A5.46 W1.5legacy table
Tytan II 1P+N 63 A7.62 W1.5legacy table
Tytan II 3P+N 25 A8.63 W3legacy table
Tytan II 3P+N 35 A9.77 W3legacy table
Tytan II 3P+N 50 A14.55 W3legacy table
Tytan II 3P+N 63 A20.03 W3legacy table
Shelly Pro 1CB C101.13 W1published loss
Shelly Pro 1CB C162 W1published loss
Shelly Pro 1CB C251.85 W1published loss
Shelly Pro 1CB C322.1 W1published loss
Shelly Pro 1CB C402.76 W1published loss
Shelly Pro 1CB C635.6 W1published loss
Shelly Pro 2CB C102.26 W1.5published loss
Shelly Pro 2CB C164 W1.5published loss
Shelly Pro 2CB C253.7 W1.5published loss
Shelly Pro 2CB C324.2 W1.5published loss
Shelly Pro 2CB C405.52 W1.5published loss
Shelly Pro 2CB C6311.2 W1.5published loss
Shelly Pro 3CB C103.39 W2published loss
Shelly Pro 3CB C166 W2published loss
Shelly Pro 3CB C255.55 W2published loss
Shelly Pro 3CB C326.3 W2published loss
Shelly Pro 3CB C408.28 W2published loss
Shelly Pro 3CB C6316.8 W2published loss
Shelly Pro 4CB C104.52 W2.5published loss
Shelly Pro 4CB C168 W2.5published loss
Shelly Pro 4CB C257.4 W2.5published loss
Shelly Pro 4CB C328.4 W2.5published loss
Shelly Pro 4CB C4011 W2.5published loss
Shelly Pro 4CB C6322.4 W2.5published loss
Smart devices
NameDissipationModulesData quality
Shelly Pro 13 W0.5electronics only
Shelly Pro 1PM3 W0.5electronics only
Shelly Pro 23 W0.5electronics only
Shelly Pro 2PM3 W0.5electronics only
Shelly Pro 33 W1.5electronics only
Shelly Pro 4PM V24 W1.5electronics only
Shelly Pro Dual Cover PM3 W1.5electronics only
Shelly Pro Dimmer 1PM2 W0.5electronics only
Shelly Pro Dimmer 2PM2 W0.5electronics only
Shelly Pro Dimmer 0/1-10V PM3 W0.5electronics only
Shelly Pro RGBWW PM1.5 W0.5electronics only
Shelly Pro 3EM 120A V23 W0.5legacy table
Shelly Pro 3EM 400A3 W0.5legacy table
Shelly Pro EM - 50A (with 2 50A CT)3 W0.5legacy table
Shelly LAN Switch1 W1.5electronics only
IHC controller3 W3legacy table
IHC power supply 15 W7 W2legacy table
IHC power supply 75 W12 W3legacy table
IHC input module 230 V2.5 W2legacy table
IHC input module 24 V10 W2legacy table
IHC output module 24 V8.25 W2legacy table
IHC output module 230 V7 W2legacy table
IHC output module 400 V14 W3legacy table
IHC backup module2.1 W1legacy table
1–10 V dimmer, IHC/SA3 W2legacy table
IHC 1–10 V output4.5 W2legacy table
IHC 1–10 V converter3.9 W2legacy table
IHC Dimmer 350 LR5 W1legacy table
IHC Dimmer 350 CR5 W1legacy table
IHC Dimmer 400 Unni3 W1legacy table
IHC Dimmer 600 CR12 W2legacy table
Dimmer 1000 LR IHC/SA3 W3legacy table
IHC Dimmer 1000 LR15 W3legacy table
IHC SMS modem0.8 W2legacy table
IHC Voice modem2 W2legacy table