Kromschroder Gas pressure switch DG400UG-4 84447597

The Kromschroder DG400UG-4 is a mechanical diaphragm pressure switch designed to monitor pressure fluctuations in gas or air environments. It has an adjustable pressure range of 50–400 mbar and features gold-plated contacts for electrical connection via screw terminals. The switch is housed in glass fibre reinforced PBT plastic with a lower housing of AlSi 12, and the diaphragm is made of NBR. It is silicone-free, has low gas release, and is rated IP65. The product complies with EN 13611:2015+AC:2016 and EN 1854:2010, and carries CE product ID CE-0085AP0467.

When selecting a replacement pressure switch of this type, ensure the pressure range, electrical connection type, and thread size match the original. The line entrance thread is typically M16 x 1.5, and the switch may have screw terminals or other connection options. Check the protection class (e.g., IP65) and the medium compatibility (e.g., gas or air). Mounting forms can vary, so verify the physical dimensions and mounting arrangement before ordering.

Common failure modes for diaphragm pressure switches include diaphragm rupture or leakage, which can cause the switch to fail to actuate or to actuate at incorrect pressures. Symptoms may include burner lockout, erratic operation, or failure to detect pressure changes. Check for visible damage to the diaphragm, leaks at the connection points, and verify the switch operation against a known pressure source.