Description
Hoyme inline damper body with Belimo CMB24-3-T 3-wire floating point actuator. Three control wires (Open, Stop, Close) give the DDC controller direct incremental blade positioning: energize Open to move the blade toward open, energize Close to move it toward closed, de-energize both to hold position. No spring return. Sizes 6"–20" in even-inch increments.
⚠ No Spring Return: Holds Last Position on Power Loss
The CMB24-3-T has no spring return. On power loss, the blade holds wherever it was. It does not move to a defined open or closed fail-safe position. If your application requires the damper to move to a defined position on power loss, whether to seal the duct on power interruption or to guarantee ventilation continues regardless of electrical state, this is not the correct product. Use a spring return actuator: HAC-40 (TFB24) for on/off, or HAC-43 (TFB24-SR-T) for modulating.
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3-wire floating point: Open / Stop / Close. The DDC controller energizes Open or Close to move the blade incrementally; de-energizes both to hold current position; blade stays exactly where the DDC leaves it
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Belimo CMB24-3-T: factory-mounted to Hoyme damper body. Single SKU, ready to install; actuator field-replaceable through Belimo distributors without disturbing duct connections
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24 Vac or 24 Vdc supply: either polarity on DC; compatible with BAS control power that outputs DC rather than AC
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End switch available on all sizes: confirms physical blade position back to BAS digital input; useful on floating point systems where the DDC infers position from pulse timing. End switch gives definitive confirmation when the blade reaches its travel limit
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Heat bypass (-H) available on all sizes: 10% bypass machined into blade at factory for hot air supply duct zone control; do not specify -H on fresh air, make-up air, or ventilation applications
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Need more torque in floating point at 24 Vac/dc? See HAC-30 (LMB24-3-T), same 3-wire architecture, 45 in-lb against this CMB24-3-T's 18 in-lb; or HAC-35 (CMB120-3) for line voltage
Confirm 3-wire terminal assignments with the DDC controls designer before wiring. The CMB24-3-T uses an OPP action code: blade direction is controlled by which wire the DDC energizes, not by a factory PO/PC setting. Confirm Open, Close, and common terminal wiring against the DDC output card specification before installation.
| If your application needs… | Product | Actuator |
|---|---|---|
| 3-wire floating point DDC, 24 Vac/dc, holds last position | HAC-34 | CMB24-3-T: this product |
| 3-wire floating point DDC, 24 Vac/dc, higher torque: 45 in-lb [5 Nm] | HAC-30 | LMB24-3-T |
| 3-wire floating point DDC, 100–230 Vac line voltage | HAC-35 | CMB120-3 |
| On/off 2-wire spring return gate, 24 Vac/dc | HAC-40 | TFB24 |
| Proportional 2–10 VDC: spring return fail-safe | HAC-43 | TFB24-SR-T |
| Fire and smoke actuator, 24 Vac (not a listed damper) | HAC-90 | FSLF24 US |
Control Type
3-wire floating point: Open / Stop / Close
Fail-Safe
Holds last position, no spring return
Actuator
Belimo CMB24-3-T
Supply Voltage
24 Vac or 24 Vdc
Sizes
6"–20" even inches
End Switch
Optional (S prefix)
Heat Bypass (-H)
Available all sizes: hot air zone only
CSA Status
Not CSA certified
Ordering the -H heat bypass variant? The -H suffix indicates the 10% heat bypass blade for hot air supply duct zone control. Do not specify -H on fresh air intake, make-up air, or ventilation applications: the bypass allows continuous outdoor air infiltration when the damper is commanded closed.
2-year electrical · 10-year mechanical warranty
Hoyme damper body: Made in Canada · Belimo CMB24-3-T field-replaceable through Belimo distributors
Product image is representative only. Actual product may differ in appearance depending on size, configuration, and options selected at order.
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