NLS XL-1 Instructions

Non-Linear Systems
XL-1
Current Loop Meter
INSTRUCTIONS
OVERVIEW
The XL-1 is a digital current loop meter
with a unique feature that requires no
power supply for its operation. All the
power it needs is derived from the
current being measured. With field-
programmable scaling
capability, you will find a variety of
applications in 4-20mA and 10-50mA
current loops. The display is 3⅟₂ digits
with a 0.6-inch LCD display.
SPECIFICATIONS
Display: 0 to ± 1999 digits, 0.6-inch
Accuracy: ± 0.1% rdg ± 1 digit
Decimal Location: May be positioned
by a Solder Blob for any of three
positions: X . X . X . X
Polarity: Automatic
Update Rate: 3 rdg/sec, nominal
Power: None required. The meter
derives the power it needs from the
current being measured.
Operating Temperature: 0°C to +45°C
Maximum Input Current: 50 mA
Minimum Input Current: 4 mA
Voltage Drop Across Meter:
• With SB4 closed (0.015Ɪ +2.5)
volts ±2%*
With SB4 open (0.030Ɪ +2.5)
•
volts ±2%*
*Ɪ is the loop current in mA
Input Z: 20 mA loop = 30 Ω
Overload Indication: With inputs
exceeding full scale Positive: +1,
Negative: -1
Weight: 3 ounces (85.05g)
MOUNTING DATA
A rectangular panel cutout is recom-
mended for mounting the instruments.
The recommended dimensions are:
The meters will also fit the DIN/NEMA
standard cutout, 92 mm x 45 mm (3.622
in x 1.772 in) and the widely used 99.7
mm x 42.72mm (3.925 in x 1.682 in)
cutout.
Any panel thickness from 1.524 mm
(0.060 in) to 4.57 mm (0.18 in) may be
used.
and offset
LCD
Figure 1. Case Dimensions
50 mA loop = 15 Ω
92 mm (3.622 in)
43 mm (1.693 in)
To mount the meter: insert the meter
from the front of the panel through the
cutout. Fit the mounting clips (2) in the
slots on the top and bottom of the meter
case. The foot of the clip should face
forward. Thread screw (2) into clips &
tighten the screw against the rear
surface of the panel to fasten the meter
in place.
CONNECTIONS
For all applications, the positive input
lead (current going into the meter) must
be connected to terminal 1. The
negative lead should be connected to
terminal 2. In applications where it is
necessary to reduce the voltage drop
across the meter, SB4 may be installed,
see Chart below.
Positive Terminal 1
Negative Terminal 2
Voltage Drop Across Meter
With 50 mA Current
SB4 OPEN SB4 CLOSED
4.13 Volts
DECIMAL POINT POSITION
If a decimal display is desired, install a
solder blob on SB1, SB2 or SB3
depending upon which decimal point is
to be illuminated.
Dec. Location: X . X . X . X
Solder Blob: SB1 SB2 SB3
If decimal point is not desired, omit blobs.
CALIBRATION
Unless special factory calibration is
ordered, the XL-1 meters are factory
calibrated so that at 4 mA input causes
a display of 000 and a 20 mA input
causes a display of 100. If a different
calibration is required, proceed as
follows:
1. Calculate A, the counts per mA, from
the equation A=C-c/Ɪ-i where i is the
smaller of two currents in milliamperes,
Ɪ is the larger current, c is the number
of counts displayed corresponding to i
and C is the number of counts corres-
ponding to Ɪ.
3.37 Volts