GRT508EC 20A PCB Latching Relay 4KV Dielectric for Smart Meters
20A contact switching, impulse excitation, PCB soldering, UL recognized component
Product Summary
The GRT508EC is a 1-pole latching relay designed for smart metering and energy management systems. It provides 20A resistive load switching with AgSnO2 contacts and requires only a pulse to change state, maintaining position without continuous coil power. The relay features 4KV dielectric strength between coil and contacts, PCB mounting, and a compact 29 x 12.7 x 15.7 mm outline. With 60,000 electrical operations at 20A 250VAC and 100,000 mechanical operations, it suits prepaid meters, smart home controls, and energy measurement modules.
Key Features
- 20A Contact Switching: Rated resistive load 20A, max switching current 20A, max switching voltage 277VAC — handles typical metering circuit loads.
- Impulse Excitation Only: Single or double coil configuration; a pulse sets or resets the contact, then the relay latches — no holding power needed.
- 4KV Dielectric Strength: High isolation between coil and contacts improves safety in metering equipment.
- PCB Soldering Mount: Direct PCB installation form supports automated assembly.
- Long Endurance: 100,000 mechanical operations and 60,000 electrical operations at 20A 250VAC.
- RoHS Compliant: Meets environmental requirements for global markets.
Technical Specifications
| Parameter | Value |
|---|
| Rated Load (resistive) | 20A |
| Contact Material | AgSnO2 |
| Max. Switching Current | 20A |
| Max. Switching Voltage | 277VAC |
| Coil Voltage | 5–24 VDC |
| Mechanical Endurance | 100,000 OPS |
| Electrical Endurance | 60,000 OPS (20A 250VAC) |
| Max. Short-Circuit Current | 500A / 2ms |
| Ambient Temperature | -40℃ ~ +85℃ |
| Installation Form | PCB |
| Outline Dimensions | 29 x 12.7 x 15.7 mm |
| Dielectric Strength (coil-contacts) | 4KV |
Models and Options
The 20A version is designated GRT508EC. Available options include:
- Coil voltage: 5 VDC to 24 VDC (specify at order)
- Coil configuration: single coil or double coil
- Contact material: AgSnO2 (standard)
For a 16A rated version with 100,000 electrical operations at 16A 250VAC, see the GRT508EA model.
Materials and Structure
The relay housing is made of flame-retardant plastic, with copper internal conductors. The contact points use AgSnO2 (silver tin oxide) for reliable switching. The structure includes a PCB-mountable base, an electromagnetic coil system, and a latching mechanism that holds the contact state after pulse removal. Outline dimensions are 29 mm (L) x 12.7 mm (W) x 15.7 mm (H). The design supports both single and double coil configurations within the same footprint.
Applications
- Smart electricity meters and energy measurement modules
- Prepaid meter on-off control circuits
- Smart home load control (lighting, HVAC, appliances)
- Industrial control panels requiring latching function
- New energy charging pile control circuits
Designed for resistive loads in ambient temperatures from -40℃ to +85℃, with relative humidity 5%~85%RH non-condensing and altitude ≤2000m.
Customization
Coil voltage (5–24 VDC) and coil configuration (single or double coil) can be specified to match your circuit design. Contact material is fixed as AgSnO2 for this model. For specific packaging or labeling requirements, please contact our sales team with your project details.
Product Images
GRT508EC20A-1 — front view
GRT508EC20A-2 — side view
FAQ
Q: What is the difference between single coil and double coil? A: A single-coil latching relay uses one coil with polarity reversal to set or reset; a double-coil version uses separate set and reset coils. Both are available for the GRT508EC.
Q: Does the relay require continuous power to stay closed? A: No. It is a latching relay; a pulse is enough to change state, and the contact remains in that state without coil power.
Q: What is the electrical endurance at 20A? A: 60,000 operations at 20A 250VAC resistive load. Mechanical endurance is 100,000 operations.
Q: Is this relay UL recognized? A: Yes, the GRT508E series holds UL Recognized Component certification (UL-CA-L340054-512-92406102-1) under CSA C22.2 No. 14-18 for industrial control switches.
Q: What coil voltages are available? A: The standard coil voltage range is 5 VDC to 24 VDC. Specify your required voltage when ordering.
Q: Can it be used in smart meters? A: Yes, it is specifically designed for smart metering, prepaid meters, and energy measurement modules, with low coil power consumption and high shock resistance.
Inquiry Information
For pricing, samples, or technical support, contact Zhejiang Great Electrical Co., Ltd.:
Email: sales5@great-relay.com
WhatsApp: +86 180 5732 9886
Address: No.9 Linhu Avenue, Yaozhuang Town, Jiashan County, Jiaxing City, Zhejiang Province, China
Company founded 2003, 50,000m² factory, 500 employees, 60 R&D engineers, 55% export ratio.
Image Filename and Alt Suggestions
- Filename: grt508ec-20a-pcb-latching-relay-front.png — Alt: GRT508EC 20A PCB latching relay front view with terminal arrangement
- Filename: grt508ec-20a-pcb-latching-relay-side.png — Alt: GRT508EC 20A latching relay side profile showing PCB mounting pins
