Secondary Injection and Relay Test Sets: Sverker vs SMRT
Megger SVERKER suits single-phase field work, and SMRT suits multi-phase and digital substations. Here is how to choose a relay test set in the UAE.
For single-phase relay testing and general substation work, look at Megger's SVERKER range. For three-phase protection, choose the SVERKER 900 or a FREJA or SMRT system. Choose SMRT when you need multi-phase power, automation or IEC 61850 on digital substations.
Secondary injection tests a protection relay by feeding it known currents and voltages at its input and checking that it operates at the right value and in the right time. The relay is tested without running real fault current through the primary system.
Secondary and primary injection
The two tests answer different questions. Secondary injection checks the relay. Primary injection pushes high current through the primary circuit, so it also proves the CTs, wiring and breaker trip path. A commissioning job often needs both. Primary injection sets such as the ODEN AT and SPI2000 sit in our circuit breaker testing category.
The Megger range we stock
| Model | Type | Where it fits |
|---|---|---|
| SVERKER 650 | Single phase, built-in control panel | Field testing without a PC |
| SVERKER 750 | Single phase | General relay and substation commissioning |
| SVERKER 780 | Single phase, with phase shift and adjustable frequency | Directional, voltage and frequency relays |
| SVERKER 900 | Three phase | Three-phase field testing |
| FREJA549, FREJA546R | Multi-phase | Portable protection testing |
| SMRT1 | Single phase with IEC 61850 capability | Compact relay testing |
| SMRT46R | Multi-phase, high power | Complex protection schemes |
| SMRT410 | Multi-phase, high current | Advanced protection testing |
| SMRT410D | Multi-phase, digital substation support | IEC 61850 sites |
Output ratings change between versions and options, so confirm the current and voltage per channel on the datasheet for the configuration you are buying.
SVERKER 750 vs 780
This is the most common comparison in the range. Both are single-phase units and they look similar. The 780 adds continuous phase shift and adjustable frequency, and Megger states it can test voltage relays from 15 Hz to 550 Hz. The 750 covers general overcurrent work. If you test directional or frequency relays, buy the 780. If not, the 750 is usually enough.
Megger also notes that two or more SVERKER units can be synchronised to work as a basic three-phase set. That helps if you already own one, but if most of your work is three-phase, the SVERKER 900 or a multi-phase system is the better purchase.
When to choose SMRT
SVERKER is the simpler field tool, and SMRT is the larger system. Choose SMRT when the scheme needs several synchronised phases at once, such as differential or distance protection, or when you want automated test routines. The STVI-10 handheld controller controls SMRT systems in the field.
On digital substations, relays receive sampled values and GOOSE messages over the network, so the test set has to speak IEC 61850. In our range, the SMRT1 has this capability and the SMRT410D has digital substation support. Check the exact option with us before you order.
How to choose
- Overcurrent and earth fault relays on LV and MV boards: SVERKER 650 or 750.
- Directional, voltage or frequency relays: SVERKER 780.
- Three-phase schemes in the field: SVERKER 900 or FREJA549.
- Differential and distance protection, or automated testing: SMRT46R or SMRT410.
- Digital substations: SMRT410D.
Useful extras
A PAM410 phase angle meter checks CT and VT polarity and phase relationships. The TM200 digital timer times operations, and the MGTR-II GPS timing reference synchronises end-to-end tests. See the whole list in relay and protection testing.
Common questions
What is a secondary injection test?
It applies a controlled current or voltage to the input of a protection relay, then checks the pickup value and operating time against the settings.
Does the SVERKER 650 need a laptop?
No. It has a built-in control panel.
Can I test a three-phase relay with a SVERKER 750?
You can test one phase at a time, and two or more units can be synchronised. A three-phase set is quicker if this is regular work.
Do you deliver test sets outside Dubai?
Yes, across all seven emirates in one to two working days. For anywhere else in the GCC, send the model and destination and we will confirm on the quotation.
Buying in Dubai
We are a supplier and stockist, not an authorised Megger distributor. If authorised-channel paperwork is a condition of your project, tell us before you order. Send the model number or your test scope on WhatsApp and we will reply with a price the same working day, or see more on our Megger page.
