Inverter Specifications and Form Factor:
Below are the official Specification according to the Manual with comments on my own experience.
- Nominal DC Input Voltage: 24v
- AC Output voltage: 220v
- Capacity: 3500 VA / 3.5KVA
- Power Factor: 1 (I highly doubt this claim and would rather settle for a more modest figure of 0.8)
- Rated Output 3500 Watt ( Again I doubt this figure, I would rather settle for a modest figure of 2800 Watt based on the PF of 0.8)
- Inverter Efficiency: 80%
- Inline Efficiency: 95%
- Surge Rating: 5000w
- Low Voltage Disconnect 20v
- Max AC Charge current 35A (Confirmed to be actually 34A)
- Dimension: 570 x 315 x 300MM
- 3 State Charging Capability: Yes
- User Adjustable Charge Profile: No
My thoughts and Observation.
The Felicity Solar Inverter seem to be yet another variant of the Powerstar W7 line of inverters which is very popular and marketed under different names: Prag, MUST Power,and Xtratra Inverters are some of the different manifestation of the Powerstar W7 inverter which can be found in the Nigerian market.
Before I go further, I would like to state that my thoughts and observations would be heavily based on my first and only experience with an Inverter prior to using the Felicity Inverter was with the Sukam Falcon plus. Hence for the most part. The sukam would be used as a reference point for comparison.
Installation and Basics:
Installation of the inverter is pretty straight forward. The battery Terminals comes with 25mm² Flexible Cables of about 1 Meter. It however allows you to use you own custom cables. The terminal point is quite big and should support up to 70mm² cable type.
The AC input and output are pretty straight forward I used 2.5mm² single core cables for both connection. The inverter can also output to standard Nigerian Standard socket.
The Inverter weighs about 22KG. I was not so sure if the walls of my apartment (an estate where construction was awarded to the lowest bid with little QA oversight) Hence I mounted it on the wall close to the floor.
The Inverter comes with a 2.5 inch display which contains very basic information and definitely not user friendly. In a nut shell, it displays, AC input Voltage, AC out voltage, Battery Voltage. Charge or discharge current are not displayed but rather represented in percentage (of rated output I think)
Battery Charge Capabilities:
The Inverter comes with a built in battery charger which is Maxed at 35A according to the manual. My Victron battery monitor indicated that it actually 33A – 34A (which is close enough)
The Inverter is said to be capable of the standard 3 stage charge for batteries i.e Bulk – Absorbtion – Float. Although it does not allow for user adjusted battery voltage settings, it does have a variety of custom battery charge preset which seem to cover the field.
- Gel USA (14v – 13.7v)
- AGM1 (14.1v – 13.4v)
- AGM2 (14.6v – 13.7v)
- Sealed Lead Acid (14.4v – 13.6v)
- Gel European (14.4v – 13.8v)
- Open Lead Acid (14.8 – 13.8v)
- Calcium Open (15.5v – 13.6v)
- De Sulphation Cycle 15.5v for 4 hours)
The charge current is fortunately adjustable although by percentage, once again my victron energy battery monitor came to the rescue by revealing all:
0% = no charge
25% = 8A
50% = 18A
75% = 28A
100% = 34A
The cool thing about the inverter is that the user is allowed to disable charging altogether. For me this is the best feature of the Inverter. I have come to observe that charging your battery through the inverter from Grid electricity uses a lot of energy which can be a drain on your electricity bill (especially when it is metered)
I have 1.8kw worth of solar panels capable of generating over 5kwh worth of energy even on a cloudy day. The total battery capacity is 5280kwh and they are cycled at between 10% – 40% depth of discharge hence at any time the most I need to refill my battery is about 2500kwh. The above is why I disabled inverter charging and left the job of battery charging exclusively to my solar panels.
Equalisation is the exception. The inverter has settings for equalisation of batteries especially flooded acid batteries which should be equalised at least once in 6 month. I tested it and it worked quite well. Although my solar charge controller is capable of equalising my batteries. I find the Inverter to be much suited for battery equalization. I was able to equalise my batteries at a stable voltage of 31v and 8A for over 2 hours without any problem.
My biggest apprehension before getting this inverter was the efficiency. The Powerstar W7 are notorious for their inefficiency especially the variants sold in Nigeria which include MUST Power, Prag and Xantra. A friend who uses a 24v 3.5kva prag confirmed to me that it uses 100w when Idle. That is about 5A doing nothing. or about 120AH if used for 24 hours just to run the inverter alone. My sukam inverter uses about 26w when idle.
Thankfully when I powered up the inverter. The Victron Battery Monitor showed it used about 50w – 58w when the battery is running. (or about 2.2A) which is manageable.
The inverter has a power safe mode, which allows the inverter to be turned off when it senses load lower than 25w other to save energy. The method for detecting load is in my opinion not the most intuitive. It comes on every 30 sec with a loud thump sound for an instance (which can be scary) and goes off again. I mostly always leave this feature off.
Off means off
When my sulkam falcon plus inveter is off, it is still able of charging the battery (if grid power is available) and also automatically transfer house load to grid .. when it is switched off. I got used to this feature and assumed it was standard with most modern inverters. The felicity proved I assumed wrong. Off with this inverter means off. No charging no Grid by pass.
Although it is marketed as a pure sinewave inverter. I was unable to verify this claim using an oscilloscope. However all my equipments ran fine without any funny noise. I tested it with Tv, Freezer, Microwave, Electric Kettle, Washing Machine, Blender, Fan and all the above ran without any issue.
I do not have an inductive load which would put the inverter to its 5000w surge capacity test. The AC which should be able to are isolated from the inverter.
The Inverter performed well without any issue when I ran my Microwave, Electric Kettle, Iron for a brief period of time. I ran the Microwave for 30 Minute on a very sunny day and it ran fine.
The inverter can be very noisy. especially when you load it to about 30% of capacity. Once the fan kicks in it can take a while before it stops. It is however much quiet at night.
What I love about the Inverter:
- Form Factor (Always wanted a wall mounted inverter. It does look good and cute)
- Ability to disable inverter charging
- Equalisation function
- Ability to use custom connection cable
- All house load works without any issue.
- Numerous Battery charge voltage preset
What I dislike:
- Off means off, no auto bypass when off
- Display could be a bit more user friendly
- Can be very noisy
- Manual is almost useless
It is a good inverter from a tier 2 solar company. I saw the manufacturing process for the inverter on YouTube and it was mostly hand made with very little automation. However Felicity do seem to be a serious company with a workshop in Lagos hence their 1 year warranty issues should be easy to sort out. I have the inverter for less than a month now and so far so good. It is reasonably priced compared to the alternative and I would recommend it.