KEP ES749 - Introduction; Unit Description

ES749 Flow Computer
2
1. Introduction
Peak Demand Option
There are applications where customer charges are determined
in part by the highest hourly averaged owrate observed during
a billing period.
The peak demand option for the ES749 is intended for applica-
tions where it is important to compute such an hourly average
owrate, to note the value of the peak occurrence and the cor-
responding time and date of that event.
The demand last hour rate is computed based on the current
total and the total 60 minutes prior. This value is recomputed
every 5 minutes.
The peak demand is the highest value observed in the demand
last hour.
The time and date stamp is the time and date at which the high-
est peak demand occurred.
The Demand Last Hour and/or Peak Demand can be directly
viewed on the display by pressing the RATE key and then
scrolling through the rates with the ^/v arrow key until the de-
sired item is viewed.
The Peak Time and Date stamp can be viewed on the display
by pressing the TIME and then scrolling through the time re-
lated parameters using the ^/v arrow keys until the desired item
is viewed.
All of these items can be included into the scrolling display list
along with the other process values and totalizers in a user
selectable list.
The peak demand may be cleared by pressing the CLEAR key
while viewing the PEAK DEMAND or by means of a command
on the serial port.
The Peak Time and Date stamp can be viewed on the display
by pressing the TIME and then scrolling through the time re-
lated parameters using the ^/v arrow keys until the desired item
is viewed.
The Demand Last Hour and Peak Demand can be assigned
to one of the analog outputs. The demand last hour or peak
demand could thusly be output on a recording device such as
a strip chart recorder or fed into a building energy automation
system.
The Demand Last Hour and Peak Demand can be assigned
to one of the relays. The customer can be notied that he is
approaching or exceeding a contract high limit by assigning the
demand last hour to one of the relays and setting the warn-
ing point into the set point. A warning message would also be
displayed.
The peak demand may be used in conjunction with the print list
and data logger to keep track of hourly customer usage proles.
The Demand Last Hour, Peak Demand, and Time and Date
Stamp information can be accessed over the serial ports. The
Peak Demand may also be reset over the serial ports.
The peak demand option may also be used as a condition to
call out in remote metering by modem.
EZ Setup
The unit has a special EZ setup feature where the user is guided
through a minimum number of steps to rapidly congure the
instrument for the intended use. The EZ setup prepares a series
of questions based on ow equation, uid, and owmeter type
desired in the application.
1.1 Unit Description:
The SUPERtrol II (ES749) Flow Computer satises the instrument
requirements for a variety of owmeter types in liquid, gas, steam
and heat applications. Multiple ow equations are available in a
single instrument with many advanced features.
The alphanumeric display offers measured parameters in easy to
understand format. Manual access to measurements and display
scrolling is supported.
The versatility of the Flow Computer permits a wide measure of
applications within the instrument package. The various hardware
inputs and outputs can be “soft” assigned to meet a variety of
common application needs. The user “soft selects” the usage of
each input/output while conguring the instrument.
The isolated analog output can be chosen to follow the volume
ow, corrected volume ow, mass ow, heat ow, temperature,
pressure, or density by means of a menu selection. Most hardware
features are assignable by this method.
The user can assign the standard RS-232 Serial Port for data
logging, or transaction printing, or for connection to a modem for
remote meter reading.
A PC Compatible software program is available which permits the
user to rapidly redene the instrument conguration.
Language translation option features also permit the user to dene
his own messages, labels, and operator prompts. These features
may be utilized at the OEM level to creatively customize the unit
for an application or alternately to provide for foreign language
translations. Both English and a second language reside within
the unit.
NX-19 option
Advanced ordering options are available for Natural Gas calculations
where the user requires compensation for compressibility effects.
Compensation for these compressibility effects are required at
medium to high pressure and are a function of the gas specic
gravity, % CO2, % Nitrogen, as well as temperature and pressure.
The compressibility algorithm used is that for NX-19.
Stacked differential pressure transmitter option
This option permits the use of a low range and high range DP
transmitter on a single primary element to improve ow transducer
and measurement accuracy.
Peak demand option
This option permits the determination of an hourly averaged ow
rate. Demand last hour, peak demand and time/date stamping for
applications involving premium billing.
Data logging option
This option provides data storage information in 64k of battery
backed RAM. Items to be logged, conditions to initiate the log and
a variety of utilities to clear and access the data via the RS-232
port are provided.