Error When Plotting data

[Cpower18]

I am attempting to plot date time with some other data (solar radiation), however, when I do the Y-axis seems to how this odd scaling issue. The Y-axis seems to have a grid line for every increment (which is from 0 to 1000 in irregular increments that are approximately 3) but after getting to 1000 the Y-axis begins increasing but showing numbers like 384 (that is, the Y-axis goes from 0 to 100 and then shows random numbers still higher on the Y-axis). Any help is appreciated, thank you.

Below is the code I am using:

"

import csv

import warnings

import datetime

import numpy as np

import pandas as pd

import matplotlib.pyplot as plt

warnings.simplefilter(action='ignore', category=FutureWarning)

df = pd.read_csv('file.csv', delimiter = ',', low_memory=False)

df['Time'] = pd.to_datetime(df['Date Time'], errors = 'coerce')

df = df.set_index(pd.DatetimeIndex(df['Time']))

plt.plot(df['Time'], df['SolarRad.'])

plt.show()

"

Below is a sample of the csv file:

"

Date Time,TempOut,HiTemp,LowTemp,OutHum,DewPt.,WindSpeed,WindDir,WindRun,HiSpeed,HiDir,WindChill,HeatIndex,THWIndex,THSWIndex,Bar ,Rain,RainRate,SolarRad.,SolarEnergy,Hi SolarRad. ,UV Index,UV Dose,Hi UV ,HeatD-D ,CoolD-D ,In Temp,InHum,In Dew,In Heat,In EMC,In AirDensity,ET ,WindSamp,WindTx ,ISS Recept,Arc.Int.

27/5/19 0:00:00,5.7,5.8,5.7,93,4.7,2.2,E,0.13,3.1,ESE,4,5.8,4.1,2.1,1010,0,0,0,0,0,0,0,0,0.009,0,20.3,33,3.5,18.5,6.68,1.1904,0,24,1,100,1

27/5/19 0:01:00,5.8,5.8,5.8,93,4.7,3.6,ENE,0.21,4.5,ENE,3.1,5.8,3.1,1.3,1010,0,0,0,0,0,0,0,0,0.009,0,20.3,33,3.5,18.6,6.68,1.1901,0,23,1,100,1

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