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Chapter 4 PAS Application Software
General Meter Setup
Series PM172 Powermeters
69
Parameter Options
Default
Description
DST end month
DST end week
DST end weekday
Month-week-
weekday
Week = 1
st
, 2
nd
, 3
rd
,
4
th
or Last (last week
of the month)
First
Sunday in
November
The date when Daylight Saving Time
ends. The DST switch point is
specified by the month, week of the
month and weekday. By default, DST
ends at 2:00 AM on the first Sunday
in November of each year.
DST End Hour
1-6
2
The hour when Daylight Saving Time
ends.
Time
synchronization
input
None
DI1
DI2
None
The external port receiving the time
synchronization pulses
Daylight Saving Time
When the daylight saving time is enabled, the meter automatically advances
the device clock one hour (by default at 02.00 AM) when daylight saving time
begins and puts the clock back one hour (by default at 02.00 AM) when it
ends. The default daylight saving time change points are preset for the
U.S.A.
The daylight saving time option is disabled in the PM172 by default. If the
daylight saving time option is disabled, you need to manually adjust the
device clock for daylight saving time.
Time Synchronization Pulses
External time synchronization pulses can be delivered through one of the
digital inputs. If a digital input is selected as the time synchronization source,
the edge of an external pulse adjusts the device clock at the nearest whole
minute. The time accuracy could be affected by the debounce time of the
digital input, and by the operation delay of the external relay.
Using Digital Inputs
The meter is provided with two digital inputs that can trigger the alarm/control
setpoints to give an alarm on input status change, or can be linked to the
energy/TOU registers to count pulses from external watt meters, or gas and
water meters.
To configure them in your device, select the device site from the list box on
the PAS toolbar, select General Setup from the Meter Setup menu, and then
click on the Digital Inputs tab.
The available options are shown in the following table.
Parameter Options Default
Description
Pulse input mode PULSE MODE,
KYZ MODE
PULSE
MODE
In pulse mode, either leading, or
trailing edge of the input pulse is
recognized as an event. In KYZ
mode, both leading and trailing
edges of the input pulse are
recognized as separate events.
Pulse polarity
NORMAL (N.O.),
INVERTING (N.C.)
NORMAL
For the normal polarity, the open
to closed transition is considered a
pulse. For the inverting polarity,
the closed to open transition is
considered a pulse.
It has no meaning in KYZ mode
where both transitions are used.
Debounce time
1-1000 ms
10 ms
The amount of time while the state
of the digital input should not
change to be recognized as a new
state. Too low debounce time could
produce multiple events on the
input change.