
FLSC-62A Wire Loop Powered 4-20mA Transmitter
SPECIFICATIONS
Temperature:
Input Voltage:
Signal Input:
Analog Output
Features: 
Enclosure:
Operating -40 to 85°C 
Storage -65 to 125°C
Minimum = 7 V + (20mA X RL) 
Maximum = 28 V + (4mA X RL) 
Protected against polarity reversal
Frequency 0-10 KHz 
Amplitude 50 mV – 35 V sine or square wave 
Sensitivity field adjustable 
Impedance 50K
4mA @ 0 Hz, 20mA @ desired full scale frequency 
Full scale range -- 100 Hz-10 KHz selectable 
Response time -- 95% of change in 1 second 
Linearity -- .3% F/S 
Tempco -- < 2% of reading over entire temperature range
Mounts directly on flowmeter 
FM Approved, CSA Certified
Class I Groups B, C, D 
Class II Groups E, F, G 
Weight 1.7 lbs.
The FLSC-62A is a 2-wire loop powered analog transmitter designed to linearly convert a 
frequency input to an equivalent 4-20mA current output. When it incorporates with a turbine 
flowmeter a current representation proportional to flow is obtainable. Data transmission in a 
current format exhibits excellent noise immunity and the capability of long distance 
transmission.
A full-scale frequency range of 100 Hz-10 KHz is selectable, via S1. The span adjustment 
establishes the frequency point at which a 20mA output is achieved. The sensitivity adjustment 
permits the FLSC-62A to discriminate between a signal input and noise by increasing (CCW) or 
decreasing (CW) the input signal amplitude necessary to process a valid signal. ‘Test’ S2 when 
depressed, illuminates D1 if loop voltage and input signal both are present.
Installation of the FLSC-62A requires only 2 wires because it is a true 2-wire transmitter: input 
power and signal output utilizes the same wires.
Rev. C Update 2/02

BENCH TEST CALIBRATION PROCEDURE
Required Equipment: Power Supply 12-28v, Digital Multimeter (DMM), Frequency Generator, &
Frequency Counter
Test Procedure:  
250 Ω
Z
0 = 100-1000Hz
Frequency
Gen/Ctr
- +
Connect DMM positive lead to power supply positive, connect DMM negative lead to J1-3,
A)
1 = 1 KHz-10KHz
SENSITIVITY
R1
set DMM function to mA DC
B)
Connect power supply negative lead to 250 Ω resistor, connect other resistor leg to J1-5 
Connect frequency generator positive & negative leads to J1-1,2; respectively. Set output
C)
to sinewave & amplitude to zero 
Set S1 for desired fr equency range
D)
Turn power supply & frequency generator ‘O N’, DMM should indicate approximately
E)
4.00mA 
Adjust ‘ZERO’ (R25) for 4. 00m A DMM indication (record data)
F)
Set ‘Sensitivity’ adjust (R1) fully clockwise
G)
Adjust signal amplitude of frequency generator to 50m v & frequency to maximum desired
H)
point (full scale frequency) (record data) 
Adjust ‘SPAN’ (R19) for 20.00m A DMM indication (record dat a)
 I)
Reduce signal amplitude of frequency generator to zero, adjust ‘ZERO’ (R25) for 4.00mA
J)
DMM indication if necessary 
Adjust signal amplitude of frequency generator to 50m v, adjust ‘SPAN’ (R19) for 20.00mA
K)
DMM indication if necessary 
Adjust frequency of frequency generator to exactly 50% of maximum frequency point in
L)
step H, DMM should indicate 12.00mA ± .06. Repeat for 25% & 75% full scale 
frequencies(record data)
E
S1
R 
O
1
S 
P
FLSC-62A
A 
N
54321
DMM
mA
- +
-
Power
Supply
12-28 VDC
+
~
DC
To check linearity @ any frequency point, incor por ate the following formula:
(F/F
 X 16) + 4 = mA
max
(Where F = Flowrate frequency in Hz) 
(F
 = Frequency in Hz at which 20mA is set)
max
Ex. Assume maximum frequency point = 2000 Hz (20.00mA) Check for linearity @ 750
Hz point
750/2000 = .375 
16 X .375 = 6 
6 + 4 = 10; DMM should indicate 10.00mA @ 750 Hz input
Rev. C Update 2/02

TYPICAL LOOP CONFIGURATIONS
-
+
J1-3
FLSC-62A
J1-5
J1-3
FLSC-62A
J1-5
+
+
RSENSE
-
+
-
+
J1-3
FLSC-62A
J1-5
J1-3
+
RLOAD
-
+
12-28 VDC
+
POWER 
SUPPLY
12-28 VDC
+
POWER
-
-
SUPPLY
FLSC-62A
-
-
RSENSE
J1-5
-
RLOAD
-
+
Rev. C Update 2/02

File:\Elect\FLSC-62A.dwg
FLSC-62A 4-20mA Transmitter
FLSC-62A-01
Rev. C Update 2/02