NOVUS AUTOMATION
1/9
N1500FT Indicator
FLOW RATE INDICATOR – INSTRUCTIONS MANUAL – V1.2x E
SAFETY ALERTS
The symbols below are used on the equipment and throughout this
document to draw the user’s attention to important operational and
safety information.
CAUTION:
Read this manual carefully prior to
installation and operation of the
unit.
CAUTION OR DANGER:
Electric shock hazard
All safety related instructions that appear in the manual must be
observed to ensure personal safety and to prevent damage to either
the instrument or the system. If the device is used in a manner not
specified in this manual, its safety features may be impaired.
INTRODUCTION
This flow rate indicator provides indication, totalization,
retransmission, alarm and RS485 communication features (optional
RTU Modbus slave). It reads most flow signals available in the
market, such as pulse, magnetic pickup and 4-20 mA. The pulse
input allows connecting sensors with outputs such as reed-switch,
NPN, PNP and tension. Both for pulse input and 4-20 mA input, unit
is selectable and a scale factor is set to turn the input signal into the
unit of choice. It provides an isolated pulse output for totalized flow
retransmission and a 4-20 mA output for immediate flow
retransmission. Alarms are set off through 2 to 4 relays, depending
on the equipment model.
AC models provide a 24 Vdc / 50 mA output.
INPUTS
The flow rate indicator allows for two basic input types:
•
Instantaneous flow input through a 4-20 mA signal. In this case,
flow totalization is obtained by integrating instantaneous flow rate.
•
Totalized flow input through a pulse signal. In this case,
instantaneous flow rate is obtained by deriving totalized flow rate.
Pulse signals may come from sensors/transmitters with NPN, PNP, dry
contact (reed switch) and tension signal output, or even magnetic
pickup outputs.
When the input is set to 4-20 mA, you should establish on screens
InLL
and
InKL
which flow values are equivalent to 4-20 mA.
When the 4-20 mA input is not used as flow input, it may be used
alternatively as auxiliary input. This way it is possible to measure the
pressure of a pipeline, for instance.
The pulse flow input may be scaled, both for instantaneous and
totalized flow rates (independently), through ‘K’ multiplication factors:
k.1nst
and
k.tot
.
Both flow time base and unit must be defined on screen
Un1t 1
.
To do so, there are six characters, the first five of which are used to
set the unit and the last one (to the right) is used to set the time base
on which the flow rate is measured. Available time bases are ‘s’
(seconds), ‘m’ (minutes), ‘h’ (hours) and ‘d’ (days).
With pulse flow input, totalization will continue even if the input rate is
below the minimum rate required. Instantaneous flow rate indication
will be zero whenever there is a time lapse of 10 seconds without
input variation. In this case, whenever there is a totalization increase
(more input pulses), the instantaneous flow value will be shown for
the nest 10 seconds.
“K” FACTORS
The instantaneous K factor (
k.1nst
) and the total K factor (
k.tot
)
allow the user to view the instantaneous and totalized flow in different
units.
The instantaneous K factor will be available only in case the selected
flow input type is different from 4-20 mA. When the input type is 4-20
mA, the configured range limits already provide the parameters for
the indication.
Instantaneous flow is directly related to the time base set in
parameter
Un1t1
.
In case user erroneously configures parameters
k.1nSt
and
k.tot
with value “0” (zero), this will be assigned value “0.00001”.
Example 1:
Chosen meter gives us an information of (pulses per volume) 50
pulses per liter. User wants to view the instantaneous flow in liters (l)
and the totalized flow in cubic meters (m³).
In order to do that, parameter
k.1nst
should be set a value of “50”,
so indicating the instantaneous flow in liters. Parameter
k.tot
should
be set a value of “50000”, so indicating the totalized flow in m³.
Instantaneous flow will be viewed based on the selected time base in
Un1t1
. In case the example meter output is 50 pulses per second,
which means 1 liter/second, and the selected time base is m
(minute), the instantaneous flow indication will be 60 (liters/minute).
Example 2:
Chosen sensor gives us an information in 4-20 mA that corresponds
to a flow between 0 and 100 liters per minute. User wants to view the
totalized flow in cubic meters (m³).
On this case, parameter
1N.TYPE
sholud be selected as 4-20 mA
and parameters
InLL
and
InKL
should be configured as “0” and
“100”. This way, we pass to the equipment the information that 4 mA
relates to 0 liters per minute and 20 mA relates to 100 liters per
minute. In case sensor output is 12 mA, flow will be displayed as 50
liters/minute.
Parameter
k.tot
should have a value of 0.001 (1 liter = 0.001 m³).
This way, the totalized flow will be converted and displayed in m³
(cubic meters).
When the instantaneous flow type is selected as 4-20 mA, the time
base selected in
Un1t1
have no influence over the indicated values,
having just unit display purposes. The indication conversion from
“liters per minute” to “liters per hour” should be adjusted directly on
input limits
InLL
and
InKL
.
In case user wanted instantaneous flow indicated in cubic meters per
hour (m³/h) with the same meter, the values “0” and “6” should have
been selected in input limits
InLL
and
InKL
, where the second
value means 100 l/min converted to m³/h.
k.tot
parameter should
be changed to “1” because input is already in m³.
