Viking 2.5in. in. Digital Clock Double Mount - CL-DMD2

Viking Electronics CL-DMD2 Double Mount Housing for 2.5-Inch Digital Wireless Clocks

Overview

The CL-DMD2 is a double mount housing designed specifically to hold two Viking CL-D2 wireless digital clocks back-to-back, projecting them perpendicular to a wall. The result is a single-point installation that serves both directions of traffic in a corridor — meaning a long hallway only needs one wiring location to keep both ends informed of the time. If you've managed clock infrastructure in a school, hospital, or manufacturing floor where synchronized time visibility across long runs is a real operational requirement, this mount solves the mechanical half of that problem. It pairs with the CL Series wireless clock system, which uses Viking's 915–928 MHz frequency-hopping RF network to keep every clock in sync, updated every minute from the CTG-2A master clock via a CL-RFT RF transmitter. The CL-DMD2 (often searched as CL DMD2) is the accessory that makes bidirectional hallway coverage practical without doubling your junction box count.

Key Features

• Bidirectional Corridor Coverage: The double mount configuration holds two CL-D2 clocks at opposing 90-degree angles to the wall. A single mounted unit covers both directions of foot traffic down a hallway — you get two visible clock faces from one installation point, which matters in long corridors where a flat wall-mounted clock would only be readable from one approach direction.
• 2.5-Inch Digital Display Compatibility: Purpose-built to house the CL-D2, which carries a 2.5-inch tall digital display. That digit height is legible at corridor distances without requiring the larger CL-D4 (4-inch display) form factor — useful when ceiling height or architectural clearance limits how large a clock housing can project into the space.
• 915–928 MHz Frequency-Hopping Wireless Sync: The CL-D2 clocks housed in this mount operate on Viking's 915–928 MHz band with frequency hopping, which provides resilience against RF interference from other facility systems operating in the same general band. Clocks sync every minute from the master transmitter, so drift between displays in the same building stays effectively zero — meaningful in facilities where time discrepancies between clocks create compliance or operational problems.
• Black ABS Case with Polycarbonate Crystal: The housing material is black ABS with a polycarbonate crystal face. ABS handles normal indoor impact without cracking, and polycarbonate crystal resists surface scratches and yellowing better than standard acrylic — relevant in high-traffic corridors where the housing is at arm height and subject to incidental contact.
• 0°C to 50°C Operating Range: The rated operating temperature covers the standard commercial indoor environment. This is an indoor-only product — don't specify it for covered outdoor walkways or loading docks that see temperature extremes beyond this range.
• Power Adapter Sourced: The CL-D2 clocks this mount holds are powered via power adapter, not battery. Plan for a local power drop at each double mount location — there is no battery backup in this system, so the clocks will go dark during a power outage unless the circuit is UPS-protected.
• Part of the CL Series Ecosystem: The CL-DMD2 is a mechanical accessory within Viking's CL Series synchronized clock system. The full system requires a CTG-2A master clock and a CL-RFT RF transmitter — the double mount housing does not include these components and does not function as a standalone product. It is the mounting solution for an already-planned CL Series deployment.

Integration and Compatibility

The CL-DMD2 is compatible exclusively with the Viking CL-D2 digital clock (2.5-inch display). It does not accommodate the CL-D4 (4-inch display variant) or Viking's analog CL Series clocks. The wireless sync infrastructure — CTG-2A master clock and CL-RFT RF transmitter — must already be in place for the hosted CL-D2 clocks to receive time updates. The 915–928 MHz band used by the CL Series is license-free in the US, but verify local RF regulations for international deployments. For Viking Electronics clock system planning, confirm RF coverage of the CL-RFT transmitter reaches all double mount locations in your facility before committing to mount placement. Review the intercom, paging, and clock systems category for the full CL Series lineup, and pair this mount with a CL-D2 wireless digital clock for a complete assembly. For facilities integrating synchronized clocks with access control or paging infrastructure, a paging system overview may also be useful for planning the broader communications layer.

Frequently Asked Questions

Q: What clocks are compatible with the CL-DMD2 double mount housing?

A: The CL-DMD2 is designed to hold two Viking CL-D2 digital clocks, which feature a 2.5-inch display. It is not compatible with the CL-D4 (4-inch display) or Viking analog CL Series clock models.

Q: Does the CL-DMD2 include clocks, a master clock, or an RF transmitter?

A: No. The CL-DMD2 is a mechanical mounting housing only. The CL-D2 clocks, CTG-2A master clock, and CL-RFT RF transmitter are sold separately and must be specified as part of the complete CL Series system.

Q: How does the wireless sync work with clocks mounted in the CL-DMD2?

A: The CL-D2 clocks receive a sync signal every minute via Viking's 915–928 MHz frequency-hopping RF network from a CL-RFT transmitter connected to a CTG-2A master clock. The double mount housing has no effect on the wireless sync process — it is purely a mechanical bracket.

Q: Is the CL-DMD2 suitable for outdoor installation?

A: No. The operating temperature range of 0°C to 50°C and the housing construction are rated for indoor commercial environments only. Do not specify this mount for covered outdoor walkways or spaces that fall outside this temperature range.

Q: What is the power source for clocks installed in the CL-DMD2?

A: The CL-D2 clocks installed in this mount are powered by a power adapter — there is no battery operation. Each installation location requires a local AC power drop. If continuous operation during outages is required, the circuit feeding the mount should be on a UPS-protected branch.

Q: Why use a double mount instead of two separate wall-mount clocks?

A: A double mount positions both clock faces perpendicular to the wall, making time readable from both directions of travel down a hallway from a single junction box location. Two standard wall-mount clocks would require two separate power and mounting locations to achieve the same bidirectional coverage.

Marty Allison

The CL-DMD2 is a straightforward mechanical solution to a real hallway-coverage problem, but it's the kind of accessory that causes headaches when specified without confirming the full system context. The housing itself is passive — what matters is whether your CL Series wireless infrastructure has the RF coverage to reach both CL-D2 clocks at their installed location, and whether you have a power drop available at each mount point.

Technical Highlights:

• 915–928 MHz Frequency Hopping: The band is license-free in the US and the hopping behavior reduces sensitivity to interference from other RF systems in the building — relevant in hospitals or manufacturing environments with dense wireless infrastructure.
• Per-Minute Sync Interval: Clocks update every 60 seconds from the master, keeping time drift between displays in the same facility effectively zero. In a large campus with dozens of clock locations, this interval keeps the system practically synchronous without requiring tight RF timing tolerances.
• Black ABS with Polycarbonate Crystal: Polycarbonate holds up better than acrylic in high-traffic corridors — it resists surface crazing and impact at arm level. Not indestructible, but appropriate for the indoor commercial environments this mount is rated for.

Deployment Considerations:

• Confirm CL-RFT transmitter placement covers each CL-DMD2 location before finalizing mount positions — the 915–928 MHz signal will penetrate standard drywall but metal-stud construction and elevator shafts can create dead zones that require a second transmitter.
• This mount requires a power adapter at every installation point; there is no battery fallback. On healthcare or critical-operations floors where clock visibility during power events matters, put the branch circuit on a UPS-protected panel — the operating specs give you 0°C to 50°C but no backup power path.

The CL-DMD2 is the right call for long-corridor deployments in schools, hospitals, or industrial facilities where a single junction box needs to serve both directions of hallway traffic — specifically when the CL Series wireless system is already the clock standard in the building and you need to extend bidirectional visibility without adding wiring runs.