Description
Tired of voicemail systems that won't release a line because your PABX station never sends a proper hang-up signal? The Viking CPC-4 solves that problem in one compact box.
This handy device gives you four independent CPC (Calling Party Control) channels in a single unit. It listens for the end of a call—busy tone, fast busy (reorder), return to dial tone, or even steady silence—and instantly sends a clean 1-second loop-current break. That tells your voicemail, call sequencer, or other automated equipment the caller has hung up, so the line becomes free again right away.
Perfect for tandem PABX setups, voicemail behind a phone system, T-1 channel banks, or VoIP gateways that lack native CPC signaling. Phone-line powered means there's no extra power supply to buy or plug in, and cage-clamp screw terminals make installation straightforward for any technician.
Our Expert Take: The CPC-4 is one of those behind-the-scenes devices that makes a real difference in day-to-day reliability. If your voicemail ports stay locked up after a caller hangs up or your automated attendant keeps cycling on dead air, this is almost certainly the fix you need. The per-channel LEDs showing In-Use, Audio Detected, and CPC Generated status are a genuine time-saver during troubleshooting—you can confirm at a glance which channels are working without pulling out a butt set. If you only need to fix a single line, Viking also offers a single-channel version worth considering, but for most multi-line PABX environments the CPC-4 covers all your ports in one shot.
Key Features
- Four independent CPC channels in one compact unit
- Phone-line powered — draws just 20VDC / 20mA from the line itself, no external power supply needed
- Generates a clean 1-second CPC disconnect signal on busy tone, reorder/fast busy, return to dial tone (programmable), or steady silence (programmable)
- Per-channel LEDs display In-Use, Audio Detected, and CPC Generated status for easy monitoring and troubleshooting
- Fully Caller ID compatible
- Easy cage-clamp screw terminal connections for quick, reliable wiring
- Works with tandem PABX setups, voicemail systems, T-1 channel banks, and VoIP gateways lacking native CPC signaling
- Built for long-term service in 32°F to 90°F operating environments
Technical Specifications
- Power: Telephone line powered (20VDC / 20mA minimum)
- CPC Disconnect Duration: 1 second
- Channels: 4 independent CPC channels
- Connections: 4-position cage-clamp screw terminals
- Dimensions: 5.25″ × 3.5″ × 1.75″ (133mm × 89mm × 44mm)
- Operating Temperature: 32°F to 90°F (0°C to 32°C)
- Humidity: 5% to 95% non-condensing
- Shipping Weight: 2.5 lbs (1.13 kg)
- Certifications: Caller ID compatible