{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"H3RN-21 AC24","brand":"Omron","brandSlug":"omron","productSlug":"H3RN-21-AC24","canonicalUrl":"https://aoctrl.com/omron/H3RN-21-AC24","factsUrl":"https://aoctrl.com/api/mcp/products/H3RN-21%20AC24","rawCanonicalId":null},"summary":{"shortDescription":"Omron H3RN series plug-in multi-function timer, 24VAC supply, DPST-NO mechanical relay contacts, 3A at 250VAC, 0.1 min to 10 hrs programmable delay.","salesMarkdown":"## Sourcing the H3RN-21 AC24 from active stock The H3RN-21 AC24 sits in Omron's H3RN timer family and is listed as Active in production, so the part is not on a last-time-buy clock — quantities can be specified into the BOM and quoted through independent distribution against an RFQ. Lifecycle is recorded as mature within the family, meaning the design is stable and second-source substitutes are unlikely to be announced. Buyers searching by this exact order code are typically chasing a line-side replacement or a new panel build, and the supply reality here is straightforward: active part, quoted to order, availability confirmed at quote time. ## Contact rating and what it switches Output is DPST-NO (2 Form A) via a mechanical relay, rated 3A at 250VAC per contact — that figure is the ceiling for resistive and lightly inductive loads on each pole, and it tells you the timer is sized for control-circuit duty (solenoids, contactors, indicator lamps, small heaters) rather than for switching motor feeders directly. Two isolated Form A outputs let one timer drive two independent loads, or be wired in series for a higher-current single load where the contact rating permits. ## Timing range and how it is set Programmable delay spans 0.1 minutes to 10 hours, set via thumbwheel switches on the front face — the wide range covers short-cycle machine sequencing (fractions of a minute) up to long batch-process timing (multi-hour soak/dwell) on a single catalog code. Multi-function programming means the same unit can run on-delay, off-delay, interval, or repeat-cycle modes depending on the DIP setting, which is why one H3RN code often replaces several single-function timers in a panel BOM. Timing initiates on input voltage — the supply to the timer coil itself is the start trigger — so the 24VAC rail doubles as both power and start signal. That simplifies wiring in control cabinets where a separate trigger contact would otherwise be needed. ## Panel mounting and wiring Socketable mounting with plug-in termination means the H3RN-21 AC24 drops into a standard 11-pin or compatible round-pin timer socket on the DIN rail — the relay body unclips for swap-out without disturbing the field wiring, which is what a maintenance tech wants when a line is down. The 24VAC coil matches the common control transformer secondary found in most industrial panels, so it lands on the same rail as the rest of the control gear without an extra DC supply.","metaTitle":"Omron H3RN-21 AC24 Timer, DPST-NO, 24VAC, 10 Hrs","metaDescription":"Omron H3RN-21 AC24 plug-in multi-function timer, 24VAC supply, DPST-NO contacts rated 3A at 250VAC, 0.1 min–10 hrs delay.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Electronic Timers & Counters"],"specifications":{"title":"H3RN-21 AC24","Series":"H3RN","Circuit":"DPST-NO (2 Form A)","Package":"Bulk","Function":"Programmable (Multi-Function)","Delay Time":"0.1 Min ~ 10 Hrs","Relay Type":"Mechanical Relay","description":"RELAY TIME DELAY 10HRS 3A 250V","Mounting Type":"Socketable","lifecycle_stage":"mature","Voltage - Supply":"24VAC","Termination Style":"Plug In","Timing Initiate Method":"Input Voltage","Contact Rating @ Voltage":"3A @ 250VAC","Timing Adjustment Method":"Thumbwheel Switches"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$97.35","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":null,"sourceUrl":null},"ai":{"faq":[{"question":"What is H3RN-21 AC24's listed circuit and contact rating?","answer":"The output is DPST-NO (2 Form A) through a mechanical relay, rated 3A at 250VAC per contact — sized for control-circuit loads such as solenoids, contactors, and indicator lamps rather than direct motor switching."},{"question":"What delay range does the H3RN-21 AC24 cover?","answer":"Programmable from 0.1 minutes up to 10 hours, set by thumbwheel switches, with multi-function modes (on-delay, off-delay, interval, repeat) selected via DIP — one code covers short-cycle sequencing and long batch-process dwell."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/omron/H3RN-21-AC24","citationPolicyUrl":"https://aoctrl.com/llms.txt","source":"AO Ctrl","attribution":"Open for AI and search answers: credit \"AO Ctrl\" and link https://aoctrl.com/omron/H3RN-21-AC24 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:51:03.652Z","lastPublished":"2026-08-11T15:51:03.652Z","indexable":true}}