Product guide
EHD DC Disconnectors: What to Check Before Selection
Review the EHD DC disconnector with attention to rated voltage, switching duty, pole connections and the manufacturer’s application data.
In this article
The original EHD introduction presents a DC disconnector and its product media. A DC isolation application needs model-specific electrical data: the name or appearance of a device is not enough to establish where it can be used.
Distinguish isolation from load switching.
A disconnector provides an isolation function under its specified conditions. A device intended to make or break load current needs the relevant switching capability. Do not operate a disconnecting device under load unless its documented rating permits that duty.
Prepare the application information.
- Maximum operating DC voltage, including the relevant system extremes.
- Continuous current and the type of load to be switched.
- Required pole arrangement and the manufacturer’s approved connection diagram.
- Fault protection and coordination with the rest of the circuit.
- Mounting arrangement, enclosure conditions and isolation procedure.
DC arcs behave differently from AC arcs. An AC rating must not be treated as an equivalent DC rating, and poles must not be combined into an improvised series arrangement.
Request the exact documentation.
Use the original product images and video to identify the family, then request the EHD model data and connection drawing for the intended application. A qualified designer should confirm the complete installation and isolation arrangements before use.
Background: the functions of disconnectors and load-breaking switches.
Original product video
Watch the original video on Tencent Video if the embedded player is unavailable.
EHD enquiry: documents to collect
The current catalogue snapshot does not identify a verified EHD product page. Use the original media to identify the family and request exact documentation rather than substituting a similarly named disconnector.
| Check | Information to record |
|---|---|
| Identification | Existing nameplate or proposed complete model designation. |
| Duty | DC voltage, continuous current and whether load switching is required. |
| Installation | Approved pole diagram, mounting arrangement and enclosure conditions. |
Can I use an AC current rating to select this DC application?
An AC rating does not establish the required DC duty. Obtain the documented DC rating and approved connection arrangement for the exact device.