Meriam M2110L SMART LEVEL GAUGE - Manual (Page 18)

9R143 Dated 3/2011
16
P6 and P7 – SETPOINT (SET1 and SET2)
SetPoint Model
These registers define the pressure points at which the SPDT relays will energize. The relay will energize
when the pressure exceeds its corresponding value, and de-energize when the pressure drops below the
value (minus deadband; see page 17). P6 defines the SET1 relay, and P7 defines the SET2 relay. P6 and
P7 settings are completely independent of each other; either may be greater, less than, or equal to the other.
Current Loop Model
These registers define the 4 to 20 mA output value. P6 (SET1) sets the 4.00 mA output and P7 (SET2) sets
the 20.00 mA output. (Thus, the output “zero” is defined by SET1, and the “span” is defined by SET2 –
SET1.) When the pressure is at the P6 value, the output will be 4.00 mA; when the pressure is at the P7
value, the output will be 20.00 mA. Other pressures provide an output that is linearly scaled between the
two values. For values beyond the defined range, however, the output is limited from 4.00 to 20.38 mA.
The P6 (4 mA) register can be set greater than the P7 (20 mA) register, to create a reverse acting output.
The limits are –20% to +120% full scale, but P6 and P7 cannot be set at equal values.
Data Entry
Refer to the Step by Step table below for detailed instructions.
These registers are entered in the current Engineering Unit used by the gauge. (The current Engineering
Unit is illuminated during edit of these registers.) For example, if the gauge is set to read in gallons, and a
value of 110 is put into the P6 register, the SET1 relay will energize at 110 gallons.
In
Program Mode, the indicators “SET1”, “SET2”, and “4-20mA” will illuminate as appropriate to assist
in identifying the register. For example, when scrolling to and/or editing P6, “SET1” will be illuminated,
indicating that SET1 is being edited. Likewise for P7 and “SET2”. Also, “4-20mA” will be illuminated if
the gauge is a Current Loop model, to indicate that the 4-20mA range is being edited.
Automatic Update
If the Engineering Unit is changed in measure mode (see page 7), the value in the P6 and P7 registers will
automatically change to reflect the new Engineering Unit. This allows changing the Engineering Unit in
Measure Mode without affecting the outputs. For the above example, changing the Engineering Unit to
liters will automatically update the P6 register to energize at 416.4 liters, which is equivalent to 110
gallons.
QUICK REFERENCE: P6/P7, SETPOINTS
Px Name Description Value Range Notes
SetPoint model:
Controls SET1 relay.
P6 SET1
Current Loop model:
Sets 4.00 mA value.
–20% to +120%
of Full Scale
SetPoint model:
Controls SET2 relay.
P7 SET2
Current Loop model:
Sets 20.00 mA value.
–20% to +120%
of Full Scale
User defined
values.
On Current
Loop models,
SET1 cannot
equal SET2.
STEP BY STEP: P6/P7, SETPOINTS
The process of programming this register is exactly the same as other real-value programmable registers. Please
refer to that procedure on page 12.
SetPoint & Current Loop Models Only