An explosion-protected gas flow switch may show an abnormal switching state or an incorrect output. The possible causes differ, so record the symptom before service. The explosion-protection approval and the exact model's instructions govern work on the device; do not open or alter certified equipment as an informal field repair.
1. Abnormal switching
Possible causes include incorrect wiring, a damaged power module, flow not reaching the configured threshold, deposits on the probe, mechanical probe damage, or an internal electrical fault.
Confirm the correct supply and terminal connections with the equipment safely isolated. Compare actual flow and the configured switching threshold within the approved process limits. Clean a contaminated probe only using the permitted procedure. Mechanical or electrical damage requires qualified service or manufacturer assessment.
2. Incorrect output
Check for wiring errors, open circuits, short circuits or relay failure. Relay replacement or circuit repair must preserve the equipment's approved protection arrangement and be carried out by qualified personnel according to the manufacturer, not by arbitrary component substitution.
Flowmethod designs, develops, manufactures and supports gas mass flow controllers, meters and custom gas-control and mixing systems. Configurations are matched to the customer's process and operating requirements.
For selection, installation or technical enquiries, contact Flowmethod: Mr. Dou, +86 180 3818 3381; doufeijin@hotmail.com. See Contact for the full contact list.