KW1M-H Eco-POWER METER
41
<Estimated demand (EV)>
It shows the estimated demand value at the end of demand span according to the using power from the
time when demand span starts to present time.
[Calculation]
Estimated
demand(kW)
=
Present
demand
+
Power change amount
for
⊿
t minutes (
⊿
P)
×
Remaining
time
(minute)
Sampling cycle
⊿
t (minute)
<Demand setting value (SV)> It shows the threshold for demand alarm output and indication.
<Remaining time (the bottom line)> Demand span (30)
-
(minus) Elapse time (t)
<Ratio of estimated demand (SET.R)> Ratio of estimated demand to demand setting value
<Alarm output / indication>
When present demand or estimated demand is satisfied the setting conditions, it output alarm and it
indicates alarm.
5.6 Clock Correction function
This is the function that it corrects the clock of Eco-POWER METER by synchronizing with the
frequency of measured voltage.
By counting the frequency of the measured voltage, it corrects the clock of Eco-POWER METER every
24-hour. It counts the frequency of the measured voltage connected to P1-P0 terminals as reference
frequency. Therefore when P1-P0 terminals are not connected or it set OFF for clock correction
function, it doesn’t correct the clock.
Caution
In order to correct the clock, it is always monitoring if the reference frequency is stable or not.
If the frequency is not satisfied below conditions, it judges it is unstable and it doesn’t correct
the clock.
<conditions>
Variation for the reference frequency :
±
0.5% during 10 seconds
Error between the internal clock and the clock by counting the reference frequency:
±
24 seconds during 24-hour
◆
Starting clock correction function
Clock correction function will start at the below timings.
・
When you change setting of ‘Clock correction setting mode’
・
When you set calendar timer of Eco-POWER METER
◆
Working at power failure and at recovery
<At power failure>
・
It stops the clock correction function and changes to use the internal clock automatically.
<At recovery>
・
It will start the clock correction function from monitoring the reference frequency.
However, it can’t correct error that was happened during it changed to use the internal clock.