Hochiki YBO-BS ESP Intelligent Addressable Base Sounder | Auto-Shutdown, Variable 50-98 dB(A) Output
Key features
- Loop powered with single loop address
- 51 selectable tones at 50-98 dB(A)
- Fits ESP sensors, beacons, remote indicators
Downloads
Summary
The Hochiki YBO-BS is an addressable base sounder built for commercial fire systems where one device needs to cover a wide range of sound requirements, offering 51 user-selectable tones and a variable output from 50 to 98 dB(A) at 1 metre from a single loop-powered unit. That range means you can match sound pressure to room size and ambient noise without carrying multiple fixed-output sounder variants on the van.
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For you on site, this translates into fewer part numbers to stock and faster commissioning, since the tone and volume are set in software rather than by swapping hardware. The base also accepts any of the ESP range of sensors, addressable beacons or remote indicators, so the same footprint on the ceiling can serve several functions as the design develops.
Addressing is automatic, carried out by the control panel or via the TCH-B200 Hand Held Programmer, which keeps first-fix wiring simple. An auto-shutdown feature lets you set a fixed sounding time before the unit silences itself, useful for cutting nuisance noise on sites with strict noise policies.
Features
- Variable 50-98 dB(A) output – set the right volume for each area from one device, no need to swap sounders
- 51 user-selectable tones – tailor the evacuation tone to site requirements, with every tone EN54-3 compatible
- Fits standard or isolator base – works on the YBN-R/3 base or the YBO-R/SCI isolator base from batch 6044 onward
- Supports ESP sensors, beacons and remote indicators – one base footprint serves multiple device types as the design evolves
- Auto-shutdown timer – sounder silences itself after a set period, cutting noise pollution on site
- Converts to a wall sounder – add the SI/CAP to create a standalone sounder point without a detector
- Approved by LPCB and VdS, with SIL Level 2 variants available
Specifications
| Ordering Codes | YBO-BS (Ivory), YBO-BS(WHT) (White), YBO-BS(BLK) (Black), SI/CAP |
|---|---|
| Operating Voltage | 17 – 41 VDC |
| Low Power Mode (Typical) | 40 µA |
| Quiescent Current (Typical) | 150 µA |
| Sounding Current (Typical) | 0.8 mA (50 dB(A) @ 1m) to 16 mA (98 dB(A) @ 1m) |
| Sound Output At 1m | 50 – 98 dB(A) (±2 dB(A)) @ 24 VDC or above, EN54-3 compliant |
| Number Of Tones | 51 |
| Tone Frequency Range | 300 – 2850 Hz |
| Operating Temperature Range | -10°C to +50°C |
| Storage Temperature Range | -30°C to +70°C |
| Maximum Humidity | 95%RH non-condensing (at 40°C) |
| Colour/Case Material | Ivory, White or Black / PC ABS |
| IP Rating | IP21 |
| Weight | 152 g |
| Dimensions | Ø 112 x H 67 mm |
| Base Fixing Centres | 48 – 74 mm |
| Approvals | LPCB, VdS; SIL Level 2 approved variants available |
FAQ
It fits either the Standard Base (YBN-R/3) or the Isolator Base (YBO-R/SCI), provided the isolator base is from Batch Number 6044 onward. Choose the isolator version where you need short-circuit isolation on that loop section. Yes, adding the SI/CAP accessory converts the base into a wall sounder, useful for points where you need sound output only, with no detector in that location. Addressing is automatic, set either by the control panel during commissioning or manually via the TCH-B200 Hand Held Programmer. No dip switches or manual coding are required on the device itself. No, although the TCH-B200 will allow addresses between 128 and 254 to be programmed into the YBO-BS, only addresses 1 to 127 should be used. Stick to that range when commissioning. No, it carries an IP21 rating and is designed for internal use only. For exposed or wet areas you will need a product rated for that environment, which this datasheet does not cover. Rated output of 50 to 98 dB(A) at 1 metre is achieved at 24 VDC or above. Current draw rises with volume, from around 0.8 mA at 50 dB(A) up to roughly 16 mA at full 98 dB(A) output, so check loop budget on larger systems with many units set to high volume.Will the YBO-BS work with a standard Hochiki base or does it need the isolator base?
Can I use the YBO-BS as a standalone sounder without a sensor fitted?
How does the unit get its loop address?
The programmer lets me set addresses up to 254, is that safe to use?
Is the YBO-BS suitable for outdoor or damp locations?
What sound output can I expect at typical operating voltages?
Downloads
- Datasheet (Adobe PDF)





