Fine Adjustment Of The Measuring Transducer; Software Package (Adapter); Sample Applications; Measurement Of Motor Currents - Phoenix Contact MCR-S Serie Mode D'emploi

6.3.7. Fine adjustment of the measuring transducer

After roughly setting the input current range and preselecting the output signal, the
module must be closed and connected to the signal lines and operating voltage following
chapter 6.1. "Electrical connection".
When the green LED lights up (operating voltage display) this shows that the operating
voltage of 20...30 V DC is connected.
Attention! When using the MCR-S-1-5-...-DCI, please be sure to use the
signal input terminal block to suit your measuring range!
Signal input range Signal input terminal
1 A
5 A
10 A
Please adhere to a warm-up phase for the module of 2 minutes before
the adjustment procedure.
6.3.7.1. Analog output
ZERO and SPAN behavior (± 25 % each) are
shown in the graphic below:
• ZERO potentiometer for zero adjustment.
• SPAN potentiometer for upper range (full
scale) value adjustment.
OFFSET (ZERO) behavior
OUT
[%]
110
100
25
IN
[%]
-100 100
-25
-100
-110
Fig. 6a
28

6.4. Software package (adapter)

As an alternative to setting via DIP switch, programming is possible using MCR-PI-CONF-
WIN, the configuration software (Order No. 28 14 79 9).
The software offers the following:
• Entering all the configuration parameters in the computer
• Saving the parameters entered in the computer in the measuring transducer
• Exporting the parameters available from the module
• Saving parameters in a drive of your choice
• Creating a side-panel label
• Printing the programmed module parameters
• Bar graph display
• Monitoring function
• Input of user characteristic curves possible
The software runs under Windows 95™, 98™, ME™, NT™, 2000™ and XP™. Interface
converter MCR-TTL/RS232-E (Order No. 28 14 38 8) serves to connect the computer and
the current measuring transducer. This converter has a stereo jack plug on one side for
connection to the current measuring transducer and a 25-pos. SUB-D socket on the other
side for connection to a computer. On the computer side, the interface converter must
generally be connected with a cable adapter (25 to 9-pos. SUB-D plug connection,
Order No. 27 61 29 5).

7. Sample applications

7.1. Measurement of motor currents

Frequency converter
Relais
5 1 MCR-S-...
L1
10 A 12
6 2
5 A 11
N
7 3
1 A 14
8 4
NC
OUT
By using MCR-S modules in one or more input phases of the motor, so-called motor
monitoring can be carried out (Fig.9). The MCR current measuring transducer can pass
on corresponding standard signals about motor load to the controller or service
personnel.
The true r.m.s. measurement means that AC, DC and distorted currents can be
measured. Even higher frequency currents up to 400 Hz can be measured.
30
Ground terminal block
block
7 7 7 7 8 8 8 8
6 6 6 6 8 8 8 8
5 5 5 5 8 8 8 8
C I
- D
W
I - S 0
- U 6 5
1 - 5
1 4
S - T
R - 2 8 O U
I
U T
M C . :
N r O U
9 U T
t -
O 2
Upper range value (SPAN) behavior
OUT SPAN
[%] +25% -25%
110
100
IN
[%]
-100 100
-100
-110
Fig. 6b
OUT POWER
9 §
TIME I + 24V
0 $
U
GND 1
sec
! %
0 30
GND 2
SW
" &
GND 2 GND 1
Control
24V
Mains voltage
Fig. 9
Adjustment:
Signal input
• After the operating voltage and the signal lines have been connected, zero or offset
must first be adjusted. No signal may be present at input (I
• The analog output must correspond to a preselected output signal from table 6.3.5. Any
inaccuracy can be adjusted with the ZERO potentiometer.
• To adjust the measuring upper range (full scale) value, a current of preferably the strength of
the upper range value should be given. If this is not possible, one of the following adjustment
equations should be used:
I
I
I = I + ( –––
O 0
I
MI
Example:
The current transducer is to be set to the following values:
Input measuring range:
Output measuring range: 0...20 mA
Constant current for configuration
The output current calculated must be adjusted with the SPAN potentiometer to
I = 12 mA. When the voltage output is used, the same adjustment procedure is
O
necessary.
6.3.7.2. Threshold value output
A current that corresponds to the threshold value is to be given for the module.
The TIME potentiometer must be set to "0 s" and the threshold value (SW) potentiometer
Fig. 5
is to be turned according to the following adjustment ruling.
Following Fig 4, page 27:
• Fig. 1: The threshold value (SW) potentiometer must be turned until the SW-LED lights up.
• Fig. 2: The threshold value (SW) potentiometer must be turned until the SW-LED goes off.
• Fig. 3: The threshold value (SW) potentiometer must be turned until the SW-LED goes off.
• Fig. 4: The threshold value (SW) potentiometer must be turned until the SW-LED lights up.
In order to avoid switching actions at the binary output level during a brief overload, a
suppression time must be set with the TIME potentiometer. If an increased current is
present for longer than the given suppression time, the preselected switching behavior
becomes active. The possible adjustment range is between 0 and 20 seconds.
When the yellow threshold value (SW) LED lights up (relay and transistor status display)
the N/O contact of the PDT contact is closed and the N/C contact of the PDT contact is
open. The transistor output switches through.

7.2. Recording motor current peak loads

L1
N
Large industrial motors have to be overhauled and serviced at regular intervals. Installing
an MCR current transducer in one phase of the motor feed line allows impulses to be
generated with the relay or transistor switching output that can be measured with the aid
of a simple meter (Fig.10). The service personnel can provide efficient maintenance on
the basis of the motor starts and peak loads corresponding to the number of overloads.

7.3. Monitoring lighting

MCR current transducers can be used for monitoring lighting. If the strength of the current
in circuit is exceeded or fallen below after a suppressed turn-on time, there is a defect in
the lighting circuit. If the lighting circuit fails, this signal status can be passed on to another
control unit and the emergency lighting can be switched on. The same procedure can also
be used with other consumers.
Operating voltage
I
E
A
U
MCR-S
V
A
= 0).
i
( I - I ) ) U = U + ( –––
* MO 0 O 0
0...5 A I = 5 A
MI
I = 0 mA
0
I = 3 A
I
5 Relais 1 OUT 9 POWER §
MCR-S-...
10 A 12
TIME I + 24V
6 2 0 $
5 A 11 U GND 1
sec
7 3 0 30 ! %
1 A 14
GND 2 SW
8 4
" &
NC GND 2 GND 1
OUT
I
A
A
Signal output
Fig. 7
I
I
( U - U ) )
* MO 0
I
MI
I = 20 mA
MO
29
Maintenance interval
meter
0 1 2 3
24V
Fig. 10
Mains voltage
31