Camden DPDT switch for CM-40 41 45 60 series rated 15 - CM-45/20

We've deployed thousands of these relays across access control installations, and the CM-45/20 remains the go-to DPDT for multi-circuit control logic in 30VDC systems. The differentiator is reliability combined with simplicity — no external relay bank, no hardwired logic board, no additional power supply. If your access control architecture is built on the CM-40/41/45/60 platform, the CM-45/20 fits directly into the existing socket design. We've seen it used for everything from dual-strike control at high-traffic entrances to simultaneous management of a main strike and a request-to-exit input on a separate circuit. One honest limitation: 15 amps is a ceiling. If you're trying to drive high-current solenoids (pool pumps, barrier arms, heavy-duty electrolocks), you'll exceed the rating — in those cases, use the relay as a logic trigger and wire an external 24/48VDC power contactor for the main load. Also, the relay itself is not networked; control is entirely logic-based through the parent module. If you need direct IP control of individual relays, you'd be looking at an IP relay controller or networked GPIO module, which is a different product class entirely.

Technical Highlights:

• DPDT Contact Configuration: Two independent pole-and-throw pairs. Each pole can independently control a circuit — one pole handles your electromagnetic strike, the second handles an ancillary load or status input. No crosstalk between circuits; each responds to the relay energization independently.
• 30VDC Strict Rating: System voltage is fixed at 30VDC. Overvoltage (even 32VDC sustained) causes rapid contact erosion and relay failure. Always check the power supply output and control buss voltage before installation — this is a common cause of nuisance lockouts on field retrofit jobs.
• 15A Continuous Capacity: Sufficient for electromagnetic strikes (typically 0.8–3A holding current) plus auxiliary devices (REX solenoid, alarm output relay, status latch). Thermal design permits sustained 15A without derating — no intermittent duty limitation.
• Socket Mount, No Soldering: Relay inserts into a standard octal or DIN socket on the control module or power supply. Screw terminals for wire termination — no PCB soldering required. Replacement is a 2-minute field swap if the original relay fails.
• Fail-Safe Control Options: By carefully wiring the normally-open and normally-closed contacts across your two circuits, you can design lockdown behavior: if the relay de-energizes (power loss, fault), the strike and ancillary solenoid default to a known safe state. Essential for life-safety applications.

Deployment Considerations:

• Socket type must match your control module or power supply — octal sockets are most common on legacy CM-40 units; newer CM-45/60 series may use DIN or proprietary connectors. Confirm socket pinout in your panel documentation before ordering a replacement relay.
• Wire gauge must be appropriate for 15A circuits; 12 AWG minimum is standard, though some codes require 10 AWG. Undersized wire creates voltage drop and relay chatter under full load — verify against your local NEC or IEC standard before installation.
• If replacing a failed relay, always investigate the root cause — overvoltage, sustained overload, or moisture ingress. Replace the relay and fix the underlying issue, or the new relay will fail identically within weeks.
• For dual-strike control, ensure both strikes are fed from the same 30VDC buss and that total inrush current (strike + solenoid) does not exceed 15A at 30VDC. If it does, use the relay as a logic trigger and wire a separate external contactor or power relay for one of the strikes.
• Label terminal pairs clearly during installation (Strike_1, REX_Input, Alarm_Bypass, Status_Out, etc.). Access control wiring can be cryptic; clear labeling saves hours of troubleshooting when the system is extended or repaired three years later.

The CM-45/20 is the right choice if you're building multi-function access control circuits on a 30VDC Camden platform and need proven, field-replaceable switching logic. For new integrations, current upgrades, or emergency relay replacement on mature access control systems, this is a core component. See the complete Camden catalog for compatible control modules, power supplies, and additional relay options.