Which back box do I need to surface mount a Hochiki HCP-E or SCP call point?
HCP-E call points flush mount as supplied; surface mounting needs a separately ordered SR-BACKBOX, and the SCP-DPS uses the SCP BACKBOX.
Direct answer
HCP-E(SCI), HCP-EO(SCI), HCP-E/Y(SCI) and HCP-EM(SCI) call points flush mount as supplied onto a standard UK single-gang switch or socket box; no Hochiki back box is needed. Surface mounting needs a separately ordered SR MOUNTING BOX (SR-BACKBOX), or the SR-1T for the HCP-E(DPS)-SCI, which has a cable screen terminal. The SCP-DPS flush mounts the same way and uses the optional SCP BACKBOX for surface mounting. Both SCP-DPS mounting methods use the wall plate (1600940-00): fix it to the backbox for surface mounting, or to the switch box for flush mounting, then clip the cover onto it. SCP-W(DPS) is surface mounted only.
Applies to
- Products / Models: HCP-E(SCI), HCP-EO(SCI), HCP-E/Y(SCI), HCP-EM(SCI), HCP-E(DPS)-SCI; SCP-DPS; SCP-W(DPS) (surface mounting only); SR-BACKBOX, SR-1T back boxes; SCP BACKBOX; wall plate 1600940-00
- Firmware / Version: Not applicable
- Region: Not applicable
- Standards: EN 54-11 (manual call points); EN 54-17 (short-circuit isolators, (SCI) variants)
Back box and wall plate options by mounting method
HCP-E(SCI), HCP-EO(SCI), HCP-E/Y(SCI) and HCP-EM(SCI): surface mounting
These call points do not include a back box. Order the SR MOUNTING BOX (SR-BACKBOX) separately for surface fixing.
HCP-E(DPS)-SCI: surface mounting
The HCP-E(DPS)-SCI uses the SR-1T back box instead of the SR-BACKBOX, because it has a dedicated cable screen terminal.
HCP-E: flush mounting
All HCP-E variants fit onto any standard UK single switch or socket box having 60 mm horizontal fixing centres and a recommended minimum depth of 25 mm, with no Hochiki back box required. Bring the loop cable out into the box before connecting the call point.
SCP-DPS: surface mounting
Fit the optional SCP BACKBOX first, then fix the wall plate (1600940-00) to the backbox with the screws provided. Clip the cover onto the wall plate to finish.
SCP-DPS: flush mounting
The SCP-DPS fits directly onto a standard UK single switch or socket box having 60 mm horizontal fixing centres and a recommended minimum depth of 25 mm. Fix the wall plate (1600940-00) to the box, then clip the cover onto the wall plate.
SCP-W(DPS)
The SCP-W(DPS) weatherproof call point is surface mounted only.
Setting the address before wiring
Set the address with a TCH-B200 hand-held programmer and a PL-3 lead while the loop is not powered, then connect the loop cables and fix the call point to the box or wall plate. See How to Wire and Program Hochiki Addressable Call Points for terminal details.
When to contact technical support
Contact Hochiki Europe Technical Support if the back box, wall plate or bracket needed for a specific model is not covered here, or if the part on hand does not match the call point being installed.
Safety note
This article is general guidance for Hochiki Europe products. Design, installation, commissioning, maintenance and modification of fire detection and alarm systems should be carried out by, or under the responsibility of, a competent person in accordance with the applicable standards (for example BS 5839-1 in the UK). Statutory requirements imposed by the relevant enforcing authority also apply. Always refer to the current product manual and data sheet for the exact model before carrying out any work.
References
- HCP-E(SCI) Installation Instructions (document 2-3-0-635)
- SCP-DPS Installation Instructions (document 2-3-0-811)
- SR-BACKBOX Data Sheet
- SCP BACKBOX Data Sheet
- How to Wire and Program Hochiki Addressable Call Points — Hochiki Europe Knowledge Base
Last reviewed: 2026-10-21 — Reviewed by: Hochiki Europe Technical Support