HK4100F-DC 3V SHG Relay 6Pin Electromagnetic Relay

The HK4100F-DC3V-SHG is a compact PCB-mounted electromagnetic signal relay featuring a 3 V DC coil, one changeover contact set and six through-hole terminals. It combines small enclosure dimensions with a contact switching current of up to 3 A and a plastic-sealed construction.

The model designation indicates:

• HK4100F – relay series;
• DC3V – 3 V direct-current coil;
• S – plastic-sealed construction;
• H – 0.20 W coil version;
• G – RoHS-compliant product.

The relay uses one 1 Form C / SPDT changeover contact. The common terminal can therefore switch between the normally closed NC contact and the normally open NO contact. This arrangement allows the relay to switch a load on or off or select between two separate circuits.

The standard through-hole terminal layout is intended for direct installation on a printed circuit board. The relay is suitable for automation modules, alarm systems, controller boards, power supplies, household electronics and other equipment where a low-voltage control signal must switch an electrically isolated circuit.

Main features

• ⚡ 3 V DC rated coil voltage
• 🔋 Low 0.20 W coil power
• 🔄 One SPDT changeover contact
• 🔌 Six through-hole PCB terminals
• 📈 Maximum switching current of 3 A
• 🛡️ Plastic-sealed enclosure
• 🧩 Compact dimensions
• ⏱️ Fast operate and release times
• 🌱 RoHS-compliant construction
• 🔧 Standard PCB terminal layout

Technical specifications

Parameter	Value
Product name	HK4100F-DC 3V SHG Relay 6Pin
Exact model	HK4100F-DC3V-SHG
Series	HK4100F
Relay type	Electromagnetic signal relay
Operating type	Non-latching, non-polarized
Mounting method	Through-hole PCB mounting
Number of pins	6
Coil type	Direct current
Rated coil voltage	3 V DC
Coil power	0.20 W
Coil resistance at +20 °C	45 Ω ±10%
Calculated rated coil current	Approx. 66.7 mA
Maximum operate voltage	2.25 V DC
Minimum release voltage	0.30 V DC
Maximum applicable coil voltage	3.90 V DC
Contact configuration	1 Form C / SPDT
Contact terminals	COM, NC and NO
Contact material	Silver alloy
Rated AC contact load	3 A at 250 V AC
Rated DC contact load	3 A at 30 V DC
Maximum switching current	3 A
Maximum switching voltage	300 V AC / 60 V DC
Maximum switching power	750 VA / 90 W
Initial contact resistance	100 mΩ maximum at 1 A / 6 V DC
Operate time	10 ms maximum
Release time	5 ms maximum
Electrical endurance	1 × 10⁵ operations
Mechanical endurance	1 × 10⁷ operations
Insulation resistance	100 MΩ minimum at 500 V DC
Dielectric strength between coil and contacts	1000 V AC for 1 minute
Dielectric strength between open contacts	500 V AC for 1 minute
Operating temperature range	–25 °C to +70 °C
Permissible relative humidity	35–85% RH
Functional shock resistance	98 m/s², approximately 10 g
Destructive shock resistance	980 m/s², approximately 100 g
Vibration resistance	10–55 Hz, 1.5 mm
Enclosure type	Plastic sealed
Enclosure dimensions	Approx. 15.5 × 10.5 × 11.8 mm
Terminal length	Approx. 3.5 mm
Basic PCB grid pitch	2.54 mm
Distance between main pin rows	7.62 mm
Weight	Approx. 3.5 g
Compliance	RoHS
Manufacturer-listed safety standards	CUL, TÜV, CQC

Contact operation

The relay contains one changeover contact set:

• COM – common terminal;
• NC – normally closed terminal;
• NO – normally open terminal.

When the coil is de-energized, COM is connected to NC. When 3 V DC is applied to the coil, the electromagnetic mechanism transfers COM from NC to NO. After the coil supply is removed, the spring mechanism returns the contacts to their initial state.

Typical applications

The HK4100F-DC3V-SHG can be used in:

• microcontroller and electronics projects;
• Arduino, ESP32 and other controller circuits;
• alarm and security equipment;
• remote-control modules;
• automation systems;
• power-supply control circuits;
• measurement and laboratory instruments;
• telecommunications equipment;
• household electronic devices;
• low-power resistive-load switching;
• galvanic isolation between control and load circuits.

Installation and operating recommendations

The 3 V coil draws approximately 67 mA, so in most applications it should not be connected directly to a microcontroller GPIO output. A transistor or logic-level MOSFET driver is recommended.

A flyback diode should be connected across the coil to suppress the inductive voltage pulse generated when the coil is switched off.

The 3 A contact rating primarily applies to resistive loads. The permissible load must be reduced when switching motors, transformers, solenoids, incandescent lamps, high-capacitance power supplies or other loads with high starting or inrush current.

Before designing a printed circuit board, verify the terminal arrangement using the bottom-view wiring diagram. This relay is not intended for certified safety circuits requiring positively guided contacts.