# Siemens 3UG5512-1BR20 Phase Monitoring Relay, 3x160-690V AC, 15-70 Hz, 2CO

**URL:** https://aio.lv/en/product--siemens-3ug5512-1br20--12481356
**Data updated:** 2026-05-27 17:49 (EEST)
**Category:** Sensors & Detectors
**Manufacturer:** Siemens
**Manufacturer code:** 3UG5512-1BR20
**EAN:** 4047621099866
**Warranty:** 2 Years
**Availability:** Available for order
**Price:** 112.49 €
**Prices and availability valid until:** 2026-08-02 23:59
**Price without VAT (21%):** 92.97 EUR
**Can be purchased by legal entities:** Yes (invoice)
**Buy:** https://aio.lv/en/product--siemens-3ug5512-1br20--12481356

## Delivery options

| Delivery method | Delivery time | Cost |
|---|---|---|
| Office pickup (2b. Kengaraga str., Riga, Latvia, LV-1063) | 22.07.2026 | free |
| Pickup points | 27.07.2026 | 1.89 EUR |
| Courier delivery to door | 27.07.2026 | 4.99 EUR |

## Summary description

The Siemens 3UG5512-1BR20 is a professional monitoring relay designed to detect phase failure, incorrect phase sequence, and phase asymmetry in three-phase networks. Operating within a voltage range of 3x160-690V AC and a frequency of 15-70 Hz, it features two changeover contacts (2CO). This device ensures reliable protection for industrial electrical systems by monitoring supply quality and preventing equipment damage due to phase anomalies.

## Long description

The Siemens 3UG5512-1BR20 is a professional line monitoring relay from the SIRIUS 3UG5 series, engineered to provide precise oversight of three-phase electrical networks. This device is specifically designed to detect critical power quality issues, including phase failure, incorrect phase sequence, and phase asymmetry. By continuously monitoring the supply voltage, it helps prevent potential damage to sensitive industrial equipment, ensuring operational continuity and safety in demanding electrical environments.
Advantages
This monitoring relay offers significant benefits for industrial automation and power management. Its compact design allows for efficient use of space within control cabinets, making it an ideal choice for modern electrical installations. The device is built for global versatility, featuring a wide operating voltage range that eliminates the need for auxiliary power in many configurations. Furthermore, the inclusion of removable screw terminals facilitates easy installation and maintenance, while the robust construction ensures reliable performance even in applications subject to vibration or varying environmental conditions.
Suitable for
Monitoring phase parameters in mobile systems such as air conditioning compressors and refrigerated containers.
Protection of electrical motors and equipment in construction site compressors and cranes.
Integration into renewable energy infrastructure, including photovoltaic systems and wind turbines.
General industrial applications requiring reliable phase sequence and asymmetry detection.
When it may not be suitable
This device is designed specifically for three-phase AC networks and is not suitable for single-phase applications or DC power systems. It should not be used in environments where the electrical parameters fall outside the specified voltage range of 3x160-690V AC or the frequency range of 15-70 Hz.
Key specifications
Operating voltage: 3x160-690V AC
Frequency range: 15-70 Hz
Output contacts: 2 changeover contacts (2CO)
Functionality: Phase failure, phase sequence, and phase asymmetry monitoring
Connection type: Screw terminals
How to use
The relay is designed for mounting within a control cabinet. Begin by ensuring the power supply is disconnected before installation. Connect the three-phase lines to the designated input terminals according to the wiring diagram. Once the physical connection is secure, the device will automatically begin monitoring the network parameters. The removable terminals allow for pre-wiring, which can streamline the installation process in complex control panels.
What to consider before purchase
Verify that your network voltage and frequency are within the supported 3x160-690V AC and 15-70 Hz range.
Ensure the 2CO contact configuration meets the requirements of your control or alarm circuit.
Check if your installation environment requires specific accessories such as sealing covers or additional labeling plates.
Usage recommendations
For optimal performance and safety, ensure that all connections are tightened to the manufacturer's specified torque. Regularly inspect the device for signs of physical damage or loose wiring, especially in high-vibration environments such as mobile compressors or cranes.

## FAQ

### How much does the Siemens 3UG5512-1BR20 Phase Monitoring Relay cost, and is it available for purchase?

The price is 112.49 € (valid at the time of publication and already includes all taxes). The item is available for order — 3 pcs. are in stock, and you can place your purchase right now with delivery across Latvia and Europe or choose pickup at the Riga collection point. We offer favorable purchase terms, including the option to split the payment into convenient monthly installments. Availability and price are updated in real time, so we recommend placing your order in advance.

### If I order this product today, when will I receive my order?

If you place your order today, delivery will be as fast and convenient as possible. You will be able to pick up your order on 22.07.2026 at the Riga pickup point or choose delivery across Latvia and Europe. We carefully inspect every purchase and pack it securely for safe transportation.

### What payment options are available?

AiO.lv offers several payment methods: Bank transfer, Bank cards on-line, Apple Pay, Google Pay, Installment. All transactions are 100% secure and encrypted.

### Can Siemens 3UG5512-1BR20 Phase Monitoring Relay be purchased with a lease?

Yes, the purchase is available both on credit and with an interest-free installment plan. Learn more about installments and credit options: https://aio.lv/en/payment#b3

### Can this product be purchased for a company (with VAT)?

Yes. AiO.lv works with legal entities in Latvia and across Europe. The product price already includes VAT. For certain product categories, as well as for companies from other EU countries with a valid VAT number, a 0% VAT rate may apply. We issue the invoice immediately after the order is placed, support electronic BIS invoices, and automatically generate all necessary accounting documents. You can complete the purchase for a company online — simply select the company profile and choose bank transfer as the payment method during checkout.

### What is the warranty period?

All Siemens products come with an official 2 Years warranty. It covers all manufacturing defects and malfunctions that may occur during use. The warranty is valid at all authorized Siemens service centers and through AiO.lv

### Can the product be returned after purchase?

Yes, you can return the product within 14 days of purchase if you bought it as a consumer (not a legal entity). Returns are possible without giving any reason — the main condition is that the product retains its original appearance and full set of accessories. We will make the process as simple and convenient as possible: just contact our customer support team, and we will help you arrange the return.

### Where should I contact for warranty service?

For warranty-related questions you can contact the AiO.lv (SIA VSPRO) customer support team. More information about warranty service: https://aio.lv/en/warranty

## Image

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