Step and Impulse Relays Selection Guide: Technical Criteria & Application Standards
Step and Impulse Relays selection guide: technical parameters, mounting and compliance standards, and Schneider Electric, Finder, Siemens comparison.
Step and impulse relays (impulse current switches, impulse relays) are modular relays that change contact position with each pulse received on the coil and keep that position after the coil power is cut. They are used to switch lighting on and off from multiple push buttons in areas such as corridors, stairwells and car parks, and to switch loads by pulse. The category includes Schneider Electric iTL and iTLI impulse current switches, ABB E290 impulse relays and Finder 20 series modular step relays; models with 16 A and 32 A rated current and 1, 2 and 4 poles are listed, along with coil voltages such as 230 V AC/110 V DC and 48 V AC/24 V DC. Select the rated current and number of poles according to the load to be switched, the contact arrangement (normally open or changeover) according to the circuit, and the coil voltage and type (AC or DC) according to the voltage of the push button circuit. In step relays with two contacts, the closing order of the contacts varies by type; verify it from the manufacturer's diagram. An impulse relay holds its position until the next pulse; it is not a substitute for a stairwell timer switch that turns the lighting off automatically after a set time. The Step and Impulse Relays category on Welibaba includes 26 active models from leading manufacturers such as Schneider Electric, Finder, Siemens.
Key Technical Parameters for Selecting Step and Impulse Relays
To specify the right Step and Impulse Relays model for your panel or installation, verify the following parameters against your engineering schedule:
| Parameter | Typical Catalog Values | Verification Note |
|---|---|---|
| Product Type | Darbe Akım Şalteri, Darbe Rölesi, Darbe rölesi için uzatma | Verify against project schedule and load calculation |
| IP Rating | IP20, IP20 (IEC 60529 (on opening)); IP40 (IEC 60529 (panoda)), IP20 (IEC 60529); IP40 (IEC 60529 (panoda)) | Verify against project schedule and load calculation |
| Switching Frequency | 100 anahtarlama işlemi/gün, 100 anahtarlama işlemi/gün; 5 anahtarlama işlemi/dakika, 5 anahtarlama işlemi/dakika, 5 anahtarlama işlemi/dakika; 100 anahtarlama işlemi/gün | Verify against project schedule and load calculation |
| Number of 9 mm Pitches | 2, 4 | Verify against project schedule and load calculation |
Installation, Compatibility, and Commissioning Checklist
- Electrical & Mechanical Matching: Confirm that rated voltage, current capacity, and mounting dimensions align with the upstream and downstream components in Automation Relays.
- Environmental & Enclosure Rating: Check IP protection class, housing material, and terminal capacity for dusty, humid, or high-vibration industrial environments.
- Related Product Groups: If your application calls for a different form factor or rating, compare sibling categories such as Industrial Relays, General-Purpose Relays, PLC PCB Relays.
Frequently Asked Questions
What is the first parameter to check when selecting Step and Impulse Relays?
Start by confirming the circuit's rated electrical values and physical mounting dimensions, then use the technical attribute filters on the Step and Impulse Relays page to narrow down compatible series.
Which Step and Impulse Relays brands are available on Welibaba?
Welibaba currently stocks 26 active models in this category from manufacturers including Schneider Electric, Finder, Siemens, complete with verified specifications and unit pricing.
How can I compare Step and Impulse Relays models by manufacturer part number?
You can search directly by manufacturer SKU/order code or use the category filter panel to compare equivalent models across brands side by side.