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apeter avatar image
apeter asked

Smart MPPT 75/15 showing very low battery voltage and disconnects load

I have connected a 150w panel, SmartSolar MPPT 75/15 and a 120AH battery-feeding DC loads totalling to about 720WH. However, as of 3-4 days the load started to be disconnected. After viewing the trend on VictronConnect it shows 0w,21v and 0Amps for Solar, 13v and 0Amps for battery but it also shows my battery has been as low as 0.01v and high of 14.6v.

We have had cloudy weather with about 4 hours of clear skies/day. I am in East Africa so normally we have ups to 8 hours of sun on non-cloudy/rainy days. I have 2 different installations all acting up the same. Any ideas?

Thank you.

Alina


MPPT Controllerslow battery warning
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3 Answers
Matthias Lange - DE avatar image
Matthias Lange - DE answered ·

I guess the fuse is blown.

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apeter avatar image
apeter answered ·

Thank you. The fuse is blown. But what would cause both fuses on separate installations to blow almost simultaneously? Both installations have a 5w rechargeable battery and a 30w Motorola radio connected on the load port of the MPPT 75/15. Could it be overloaded? I am planning to replace the fuse but I would like to know so that I can prevent it from happening again?

Thank you again for your reply.

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Warwick Bruce Chapman avatar image Warwick Bruce Chapman commented ·

I suspect peak power requirements of the radio during transmission is higher than 15A.

What are the specs?

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apeter avatar image
apeter answered ·

@warwick It's a DM3401-30W radio, so the max is 14.5A during transmission and 0.81A on standby. However, the radio is used only so often in a day.

@TTbb No, the radio doesn't have its own battery.

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Related Resources

MPPT Product Page

MPPT Error codes

MPPT 150/60 up to 250/70 Manual

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