HE721C2400 LITTELFUSE Relay or Contactor (Other) In Stock
Littelfuse HE721C2400 is an SPDT reed relay with a 24V DC coil, 2000Ω coil resistance, and 288mW coil power consumption. It features a 16V operate voltage, 2V release voltage, and a compact 19.05mm × 7.22mm × 5.5mm body. Available from stock with worldwide shipping.
- Manufacturer
- LITTELFUSE
- Package
- Other
- Pin Count
- 8
- Lifecycle
- OBSOLETE
- Datasheet
- HE721C2400 Datasheet PDF
- Category
- Relay or Contactor
- Price
- From $1.5000(MOQ 1)
- Temp Range
- -40.0°C to 85.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- SPDT reed relay configuration with 24V DC nominal coil for direct microcontroller-driven relay applications
- 2000Ω coil resistance and 288mW coil power allowing low-current drive from standard relay driver ICs
- 16V coil operate voltage and 2V release voltage providing a wide hysteresis window for reliable switching
- Compact 19.05mm × 7.22mm × 5.5mm body enabling dense PCB layouts in instrumentation and telecom equipment
Applications
The HE721C2400 SPDT reed relay is commonly used in test and measurement equipment, telecommunications switching matrices, and medical diagnostic instruments where low-power 24V DC coil actuation and reliable reed contact switching are required. Its compact form factor and 288mW coil power consumption also make it suitable for battery-assisted industrial control panels and signal routing applications that need clean galvanic isolation.
Specifications
| YTEOL | 0 |
| Body Breadth | 7.22mm |
| Body Height | 5.5mm |
| Body Length or Diameter | 19.05mm |
| Coil Current(DC)-Max | 0.012A |
| Coil Operate Voltage(DC) | 16V |
| Coil Power | 288mW |
| Coil Release Voltage(DC) | 2V |
| Coil Resistance | 2000Ω |
| Coil Voltage(DC)-Max | 44V |
| Coil Voltage-Nom | 24V |
| Coil/Input Supply Type | DC |
| Contact (AC) Max Rating R Load | 0.18A@120VAC |
| Contact Current(AC)-Max | 0.18A |
| Contact Current(DC)-Max | 0.25A |
| Contact (DC) Max Power Rating R Load | 5W@175VDC |
| Contact (DC) Max Rating R Load | 0.25A@175VDC |
| Contact Resistance | 200mΩ |
| Contact Voltage(AC)-Max | 120V |
| Contact Voltage(DC)-Max | 175V |
| Contact/Output Supply Type | AC/DC |
| Input Switching Control Type | Random |
| Insulation Resistance | 10000000000Ω |
| Mounting Feature | THROUGH HOLE-STRAIGHT |
| Operate Time | 3ms |
| Packing Method | BULK |
| Reference Standard | CUL; UL |
| Relay Action | MOMENTARY |
| Relay Form | 1 FORM C |
| Relay Function | SPDT |
| Relay Type | DRY REED RELAY |
| Release Time | 3ms |
| Sealing | HERMETICALLY SEALED |
| Surface Mount | NO |
| Terminal Length | 0.002999745999491999inch |
| Termination Type | SOLDER |
| Package | Other |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| ECCN | EAR99 |
| HTS Code | 8536.49.00.50 |
Alternate & Equivalent Parts
Compatible alternatives and drop-in replacements for HE721C2400:
suggested
Frequently Asked Questions
What coil voltage and resistance specifications define the HE721C2400's drive requirements?
The HE721C2400 requires a 24V DC nominal coil voltage with a 2000Ω coil resistance, resulting in a coil current of approximately 12mA and 288mW coil power dissipation. The operate voltage is 16V and release voltage is 2V, giving the relay a reliable switching hysteresis window.
How does the HE721C2400's SPDT reed contact benefit signal routing in test equipment?
The SPDT reed contact configuration of the HE721C2400 allows it to route analog or digital signals between a common terminal and either of 2 switched contacts, enabling low-noise signal path selection in automated test equipment, data acquisition multiplexers, and 24V-driven relay boards with minimal signal degradation.
What physical dimensions does the HE721C2400 occupy on a PCB?
The HE721C2400 measures 19.05mm in length, 7.22mm in breadth, and 5.5mm in height, offering a compact through-hole relay footprint suitable for single-sided PCBs in industrial control and instrumentation applications that must accommodate multiple relay channels within limited board area.
For a 24V industrial control panel, what makes the HE721C2400 preferable to a solid-state relay?
The HE721C2400 reed relay provides true galvanic isolation, very low contact resistance, and bidirectional switching for both AC and DC signals up to its rated load, whereas solid-state relays introduce a voltage drop and leakage current. At 288mW coil power and 2000Ω coil resistance, the HE721C2400 is also easy to drive from standard 24V relay output modules without additional buffer circuits.
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About LITTELFUSE
LITTELFUSE is a leading electronic component manufacturer. FindMyChip sources LITTELFUSE ICs directly from authorized China distributors, offering competitive pricing and reliable stock.
| Qty. | Unit Price | Ext. Price |
|---|---|---|
| 1+ | $2.3100 | $2.31 |
| 100+ | $1.7300 | $173.00 |
| 1000+ | $1.5000 | $1500.00 |
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