Generators, solar plants and batteries all need something to decide when each source runs, how load is shared and when to disconnect. That job belongs to the DEIF controller. Without one, a site with more than one power source depends on manual switching, which is slow and risky when the grid fails or the load changes suddenly. A controller watches voltage, frequency and load, then starts, stops and connects each source in the right order, so equipment is protected and fuel and solar energy are used well. This guide compares the main DEIF ranges that Sun-AP Ecopower supplies, so you can match the right unit to your site before you order.
What Does a DEIF Controller Do?
A controller monitors voltage, frequency and load, starts or stops power sources, and protects equipment from faults. DEIF was founded in Denmark in 1933 and serves industrial, renewable and marine applications, according to the DEIF page on our site. In India, these controllers are common on diesel generator sets, on hybrid plants where solar works alongside a generator, and on sites that must change over to backup power automatically.
DEIF Genset Controller: AGC 150 and AGC 150 ATS
The DEIF genset controller range is built for diesel generators. Within it, the DEIF AGC 150 is an automatic genset controller, and the AGC 150 ATS version adds automatic transfer switch control. Choose this family when a generator must start, take load and stop without an operator. Check the datasheet for paralleling and communication options before you finalise.
DEIF ASC 150 for Solar, Battery and Microgrid Plants
The DEIF ASC 150 is an automatic sustainable controller. The ASC 4 family comes in battery, solar and wind versions, and our DEIF page describes the ASC series as covering microgrid and solar-diesel applications. Use it when renewable sources must work with a generator and you want stable supply while using less diesel.
Comparison: AGC 150, ASC 150 and CSQ-3
The table below summarises the role of each product as described on our DEIF page. Always confirm details on the datasheet for your exact model.
| Product | Main job | Typical site |
|---|---|---|
| AGC 150 | Automatic genset control | Diesel generator sets and standby power |
| ASC 150 | Automatic sustainable control | Solar-diesel and microgrid plants |
| CSQ-3 | Check synchronizing relay | Safe breaker closing between two supplies |
Synchronizing Relays and Monitoring Units
A DEIF synchronizing relay such as the CSQ-3 checks that two supplies match in voltage, frequency and phase before a breaker closes, which protects generators and loads from damaging transients. Our DEIF range also includes the Solar Remote Monitoring Unit, the Multi-function Synchroscope and the AMC 300 programmable automation controller for larger projects.
Looking for a DEIF Meter?
Many buyers search for a DEIF meter when what they need is measurement and monitoring. On our meters page, DEIF appears with the AGC-150 and SGC-120 genset controllers, while the Solar Remote Monitoring Unit and the Multi-function Synchroscope cover monitoring tasks. For billing or energy-audit metering, our Secure and HPL meters are usually the better fit. Tell us your requirement and we will confirm exactly what is available.
Where to Buy DEIF Controllers in India
Sun-AP Ecopower is an authorised distributor for DEIF in India, and our DEIF page directs dealer enquiries to us. Download the datasheets, then share your generator rating, solar capacity and battery details with our team. If your project also needs energy metering, read our guide to multifunction meters.
FAQs
Is a DEIF controller only for large plants?
No. Our DEIF page says the range suits both domestic and industrial use, so match the model to your load and sources.
Can one DEIF controller manage solar and a generator?
The ASC series is aimed at solar-diesel and microgrid setups. Share your site details and we will recommend a model.
What is the difference between the AGC 150, ASC 150 and CSQ-3?
They do different jobs. The AGC 150 is a genset controller that handles generator control, protection and power management. The ASC 150 controls solar and storage in a hybrid system. The CSQ-3 is a check synchronising relay that confirms two supplies are matched before a breaker closes. Many sites use more than one of these together, so the choice depends on your sources and breaker arrangement.
When do I need a synchronising relay like the CSQ-3?
You need one where two supplies are connected in parallel, such as a generator to a busbar, a generator to the grid, or two generators together. Closing a breaker out of step can damage equipment, so the relay checks voltage, frequency and phase angle first. A site with a single generator that never runs in parallel usually does not need one.
Do I need a power management controller for a single generator?
Not always. A single genset that never runs in parallel or alongside solar can often use a simpler controller for start, stop, protection and monitoring. Power management and synchronising features matter when several generators, solar, batteries or the grid must share the load. Choosing only the features your site needs keeps the cost sensible.
What is a zero export controller, and when is it needed?
A zero export controller keeps solar power from flowing back into the grid. It is used where export is not permitted or not approved, and it adjusts the solar output to match site consumption. Confirm your local utility rules before designing the system, because requirements can differ.
What details should I share before choosing a DEIF controller?
The more you share, the faster we can shortlist a unit. Useful details include:
- Number and rating of generators
- Whether you have solar, battery storage or grid supply
- Whether the sources must run in parallel
- Number of input and output points you need
- Whether you need remote monitoring or zero export control
Can a DEIF controller be fitted to an existing generator or solar plant?
Often yes, since many projects are retrofits. The existing genset, inverter and breaker setup must be compatible with the controller, so share your current arrangement with our team before ordering.
A well-chosen DEIF controller keeps power sources working together safely. Send us your site details and our team will help you shortlist the right unit.
