Engineering tools

Relay Selector

Check the DDC-to-coil interface and the relay contacts against your actual load.

Quick start

Enter the DDC output and supply, then the candidate coil and applicable contact ratings. Leave unknown numerical values blank and select Check selection. Review matching checks, mismatches and items still marked Confirm separately.

Inputs

Enter requirements and candidate data. Leave unknown numerical ratings blank.

Selection inputs

1 · DDC output & coil supply

DDC output type Powered output nominal voltage (V) DDC continuous limit (mA)For VA/W ratings: current = rating ÷ applicable voltage. Enter mA. DDC pickup / making limit (mA)Manufacturer limit for the actual coil pickup duration. Do these DDC limits apply to this coil load?Confirm coil/inductive switching duty, not just a resistive contact rating.

2 · Candidate relay coil

Coil supply type Coil rated voltage (V) Coil consumption unitSteady and pickup inputs below share this unit.

Steady coil consumption Maximum pickup consumptionEnter manufacturer data. Leave unknown values blank.

3 · Contact load & required arrangement

Load supply type Load voltage (V) Load category Running load current (A) Maximum load inrush (A)No assumed inrush multiplier. Required contacts Mounting requirement

4 · Candidate relay contact ratings

Candidate contacts Ratings apply at this load voltage, AC/DC type and load category?Use the correct NO/NC contact and switching-duty rating. Independent maximum V and A ratings cannot be combined. Applicable switching current (A) Applicable making / inrush current (A)Confirm the permitted duration and repetition.

Illustrative mismatch example: a 24 VDC, 40 mA coil on a 30 mA DDC output. Contact ratings remain unconfirmed until applicable manufacturer data is entered.

Selection review

Enable JavaScript to check selection.

Results compare the specifications you enter. No product database, model recommendation or manufacturer approval is implied.

How this guide works

Compare nominal coil supply and voltage, then steady and pickup current separately. Compare contact switching and making current only when you confirm that the ratings apply to the actual voltage, AC/DC type, load category and duty. Unknown values remain “Confirm”; they are never assumed to be zero. A higher-pole contact form may cover a simpler arrangement, but all poles operate together.

Selection reference: OMRON general-purpose relay application guidance.

Supported checks, examples and limitations

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