July 23, 20197 yr I have installed a Axpert MKS Plus 3kVA 2400W 24V Hybrid Inverter and Blue nova BN26V-154-4k No solar panels at present only running off ESKOM for the time being All household water is from 4 x 1000l rainwater tanks A 0.75kW pump kicks in when a tap is opend When the pump kicks in the Axpert beeps once sometimes twice probably indicating overload?????? This has to relate to the startup of the pump The inverter is rated 3kW Any views on the subject would be appreciated
July 23, 20197 yr 14 hours ago, JohanG said: A 0.75kW pump kicks in when a tap is opend An induction motor's surge current is usually about 7x the rated current. So it will be of the order of 750 x 7 = 5250 VA (with a poor power factor, though starting under load it will draw plenty of real power as well). That's pretty close to the surge rating of the inverter (6000 VA). Can you check the battery voltage to see if it dips during a startup? A multimeter with a min and max function would be ideal, to catch the instantaneous voltage drop. Is your wiring up to scratch? 3000 W plus about 10% at 25 V is some 132 A, so your battery cable needs to be able to handle that continuously. You'll need a stout fuse as well. Check for arcing / burn marks on the fuse and fuse holder; perhaps the Nova isn't so good at limiting in-rush current. It may be possible to suppress the beeps with settings, but first you should ensure that it's not trying to tell you something important. A new LFP battery will take some time to get its cells all balanced; during that time, it may not get charged fully. So the situation may improve over time.
July 24, 20197 yr Author Thanks Coulomb Since I started with solar I stand amazed at the complexity of the subject as well as the knowlage on this forum
July 24, 20197 yr Author Would installing a pressure tank be a solution The pump will then only be needed when the pressure drops reducing the frequncy that the pump is activated?
July 24, 20197 yr On 2019/07/23 at 10:15 AM, JohanG said: A 0.75kW pump kicks in when a tap is opend 16 minutes ago, JohanG said: Would installing a pressure tank be a solution As a rule I install a 60 liter pressure tank for all my clients with pressure pumps when I install solar. Its much kinder to the batteries at night as well. I would recommend it. I prefer them running longer, but less frequent, rather than starting every time you open a tap.
August 15, 20196 yr On this topic, is such a "large" motor/pump needed for a water tank application like this? I want to put in a water tank and having solar I need to consider this.
August 15, 20196 yr On solar, as Jaco says, it is preferable to have a smaller pump running for longer, than a big pump pulling lots of current for a short time.
August 16, 20196 yr 13 hours ago, DeepBass9 said: On solar, as Jaco says, it is preferable to have a smaller pump running for longer, than a big pump pulling lots of current for a short time. yes but that involves a pressure tank, i am basically asking could you do it without a pressure tank but with a smaller motor?
August 28, 20196 yr I pump from my borehole to a 5000l pump that feeds the house. The pressure pump I use is on my inverter. I use the DAB Esybox mini 3. It's quite expensive but well worth it. Its an inverter pump, and best of all keeps the pressure the same all of the time. even better than munic supply. As the requirement increases, the pump ramps up.
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.