D4850C CRYDOM 50A SOLID STATE RELAY (USED)

The Crydom D4850C is a high-performance Solid State Relay (SSR). Unlike the mechanical relays (T90, JQX-52F) we discussed earlier, this device has no moving parts. It uses semiconductor power transistors (SCRs) to switch AC loads.

Because it switches electronically, it is silent, lasts significantly longer than mechanical relays, and is capable of extremely fast switching.

• Load Current:50A (Continuous, provided proper heat sinking is used).

• Load Voltage:48V to 530V AC (Designed for 220V/240V or even industrial 480V systems).

• Control Voltage:4V to 32V DC (Easily triggered by an Arduino, PLC, or the EGS002 board).

• Switching Type:Zero Voltage Turn-On. It waits for the AC sine wave to cross zero before switching, which drastically reduces Electromagnetic Interference (EMI) and electrical noise.

In a 2kW Pure Sine Wave Inverter system, the D4850C offers several professional-level advantages:

Mechanical relays have a "click" limit (usually 100,000 cycles) before the contacts pit or weld. Since the Crydom is solid-state, it can switch millions of times without wearing out. This is ideal if you are building a system that switches frequently (like a thermostat-controlled heater).

If your inverter is installed in a living area or camper, the loud "clunk" of a 40A mechanical relay can be annoying. The D4850C is completely silent.

Because there is no physical contact moving, there is no spark (arcing) when it turns on. This makes it safer for use near battery banks where hydrogen gas might be present.

The biggest "catch" with a 50A SSR is heat. While a mechanical relay has almost zero resistance, an SSR has a small "voltage drop" (about 1.1V to 1.6V).

• The Math: At 50A, the relay will generate 50A X 1.2V = mathbf60W of heat.

• The Solution: You must mount the D4850C on a large aluminum heat sink using thermal paste. Without a heat sink, a 50A SSR will burn out in minutes even at only 10A of load.

Terminal Connections

The D4850C uses the standard "Hockey Puck" footprint:

• Terminals 1 & 2 (Large Screws): AC Load terminals. These go in series with your 220V appliance.

• Terminals 3 & 4 (Small Screws): DC Control terminals.

  • 3: Positive (+)

  • 4: Negative (-)