Baldor BC145 User manual

SIGNAL ISOLATOR
BC145 Signal Isolator Board
Installation and Operating Manual
7/2000 MN1373

TABLE OF CONTENTS
Se tion Page
i. Safety Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
I. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
II. Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
III. Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
IV. Output Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
V. Limited Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Tables
1. General Performance Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Voltage Input Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Figures
1. Control Layout & Mechanical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2A. 115V Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2B. 230V Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. Current Input Signal Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4. Voltage Input Signal Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
5A. Leader/Follower Voltage Following System with Multiple Motors . . . . . . . . . . . . . . . . . . . . . . . . . .
5B. Leader/Follower Voltage Following System (Single Main Potentiometer) . . . . . . . . . . . . . . . . . . . .
6A Leader/Follower Voltage Following System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
6B. Process Control with Auto/Manual Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
6C. Process Control with Auto (Ratio Pot)/Manual Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
6D. Auto/Manual Operation with Potentiometer on BC145 Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
ii

1
This product complies with all CE directives pertinent at the time of manufacture. Contact
factory for detailed installation instructions and Declaration of Conformity.
i. SAFETY WARNING! Please read arefully:
Be sure to follow all instructions carefully. Fire and/or electrocution can result due to improper
use of this product.
This product should be installed and serviced by a qualified technician, electrician, or electrical
maintenance person familiar with its operation and the hazard involved. Proper installation,
which includes wiring, mounting in proper enclosure, fusing or other over current protection and
grounding, can reduce the chance of electric shocks, fires, or explosion in this product or prod-
ucts used with this product, such as electric motors, switches, coils, solenoids, and relays. Eye
protection must be worn and insulated adjustment tools must be used when working with con-
trol under power. This product is constructed of materials (plastics, metals, carbon, silicon, etc.)
Which may be a potential hazard. Proper shielding, grounding, and filtering of this product can
reduce the emission of radio frequency interference (RFI) which may adversely affect sensitive
electronic equipment. If information is required on this product, contact our factory. It is the
responsibility of the equipment manufacturer and individual installer to supply this safety warn-
ing to the ultimate user of this product. (SW effective 11/ 2)
!

I. INTRODUCTION
The BC145 Signal Isolator is used to isolate, amplify and condition DC voltage and current sig-
nals from any source (motors, tachs and transducers) which will provide most adjustable speed
motor controls with a voltage following input. The maximum output voltage of the isolator is 10
volts, which is a linear function of the input signal.
The BC145 is versatile since it can accommodate a wide range of input voltages (0 - 25*, 0 -
120 and 0 - 550V DC) and, in addition, a wide range of input current signals (4 - 20 mA, 10 -
50 mA and 1 - 5 mA). The Voltage/Current (“VLT/CUR”) jumper is used to change the
BC145 from a voltage to current input.
BC145 is a unipolar input, providing 0 – 10V input. For Regenerative Drives with bipolar ±10V
input, other Signal Isolators are available.
A built-in power supply enables the BC145 to be controlled with a 5KΩ remote potentiometer
(connect potentiometer to terminals “P1,” “5” and “6” – see page ). The potentiometer can
also be wired for Auto/Manual Operation.
*The input range of 0 - 25V is the maximum voltage that can be applied to terminals “5” and
“6” The minimum input voltage is 0 - 5 volts, which can achieve an output voltage of 0 - 10
volts The unit is factory calibrated so that a 0 - 10V DC input yields a 0 - 10V DC output
II. MOUNTING
Mount the Signal Isolator using (4) 6-32 screws (not included). Use the Control Layout and
Mechanical Specifications drawing on page 3 to locate the mounting holes. The unit is
designed to be mounted in any position providing its components do not come in contact with
grounded or live wiring.
2

FIGURE 1 – CONTROL LAYOUT & MECHANICAL SPECIFICATIONS (INCHES / [mm])
(Illustrates Factory Setting of Jumpers and Approximate Trimpot Settings)
3
1
MAX
P1
VOLT CUR
J1
MIN
2345678 10
(4) mounting holes for #6 screws
2.244
[57.0]
0.276
[7.00]
0.276
[7.00]
4.2 1
[10 .00]
4.843
[123.00]
2.7 5
[71.0]

Notes:
1. To achieve full specifications input voltage must be within ± 10% of nominal.
2. Floating (non-grounded) or grounded input signal may be used.
3. To change from 4 - 20mA to 1 - 5mA remove R3. To convert to 10 - 50mA add a 150Ω 1W resistor across
terminals “5” and “6.” See figure 3.
4. Specifications are based on an output of 10 volts.
AC Power Requirements . . . . . . . . . . . . . . . . . . . . . . . . . 115 or 208 - 230V AC, 50/60 Hz (1)
Signal Input Voltage (2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 - 25, 0 - 120, 0 - 550V DC
Signal Input Current (2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 - 5, 4 - 20, 10 - 50mA (3)
Maximum Output Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Volts
Maximum Output Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10mA
Range of “MIN” Trimpot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ± 3 Volts
Range of “MAX” Trimpot . . . . . . . . . . 0 to 2 times the input voltage with maximum of 10 Volts
Linearity (4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ± 0.1%
Temperature Drift (4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 mV per ºC
Temperature Operating Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 - 50 ºC
4
TABLE 1 – GENERAL PERFORMANCE SPECIFICATIONS

III. WIRING.
Warning! Read Safety Warning on page 1
before attempting to use this ontrol.
A. AC Power – The BC145 is powered with either 115 or
230V AC, 50/60 Hz by arranging the jumpers between
terminals “1” to “4” properly. See figures 2A and 2B. Be
sure unit is wired in accordance with the National
Electric Code and other codes that may apply. It is rec-
ommended that a 1 amp fuse be installed in series with
the AC line.
B. Input Terminals – A voltage or current signal from a
microprocessor, tachometer, transducer, etc. is to be
connected to terminals “5” through “8.” The selection of
the proper terminal is based on the maximum level of
the input signal. See figures 3 and 4.
5
1234
1A
FUSE
115V AC
Jumper Jumper
FIGURE 2A – 115V CONNECTION
1234
1A
FUSE
230V AC
Jumper
FIGURE 2B – 230V CONNECTION
Warning! To avoid errati operation do not bundle AC
Line and motor wires with potentiometer, voltage fol-
lowing, enable, inhibit or other signal wiring. Use
shielded ables on all signal wiring over 12” (30 m) –
Do not ground shield.
!

i. Current Input Signal
Warning! Read Safety Warning on Page 1
before attempting to use this ontrol.
Note: The Voltage/Current (VLT/CUR) jumper must be in “CUR”
position. Connect the negative current signal input to terminal “5”
and the positive to terminal “6.” The BC145 is factory calibrated so
that a 4 - 20mA signal will provide a 0 - Volt output. The input
range can be converted to a 10 - 50mA range by attaching a 150Ω
1W resistor across the current input terminals “5” and “6.” See fig-
ure 3. Control must be recalibrated when the 150Ω resistor is installed. The range of signal
input can be changed to 1 - 5mA by removing resistor R3 from the printed circuit board.
Recalibrate the Signal Isolator to follow a 4 - 20mA current signal input as follows:
1. Connect a 10V DC meter (digital DC meter is suggested) to terminals “ ”(-) & “10” (+).
2. Apply the minimum input current (4mA) at terminals “5” and “6.”
3. Adjust the “MIN” trimpot to an output voltage of 0 volt DC.
4. Set the input current to 20mA and adjust the “MAX” trimpot so that the output voltage is at
the desired level ( V DC).
5. Repeat steps 3 and 4 if extreme accuracy is required. The Signal Isolator is now cali-
brated to provide 0 - V DC output with a 4 - 20mA input.
6. Use the “MIN” and “MAX” trimpot if other than 0 - V DC output is required with the respec-
tive input current range.
6
56
150Ω Resistor
Converts 4 - 20mA
to 10 - 50mA
+–4 - 20mA
FIGURE 3 – CURRENT INPUT
SIGNAL CONNECTION
!

ii. Voltage Input Signal
Warning! Read Safety Warning on Page 1
before attempting to use this ontrol.
Note: The Voltage/Current (VLT/CUR) jumper must be in the VLT position (factory setting).
The BC145 is designed to accept a wide range of input voltage signals as follows:
Connect input voltage signal to proper input terminals as
indicated in figure 4.
1. Connect a 10V DC meter (digital meter is suggested)
to terminals “ ” (-) and “10” (+).
2. Apply the maximum input voltage that would be supplied from tach, transducer, etc.
3. Adjust the “MAX” trimpot to the desired output voltage.
Example: A follower motor is to follow the output of a leader motor with an armature volt-
age range of 0 - 0V.
7
Minimum Input
Voltage Range
Input Terminals
5, 6
Maximum Input
Voltage Range
0 - 5 0 - 25
5, 7 0 - 25 0 - 120
5, 8 0 - 120 0 - 550
TABLE 2 – VOLTAGE INPUT SIGNAL
56
+
+
–+
78
0 - 550V
0 - 120V
0 - 25V
FIGURE 4 – VOLTAGE INPUT
SIGNAL CONNECTIONS
!

a) Connect the armature of the leader motor to the BC145 input terminals “5”(-) and “7”(+).
b) Set the armature voltage of the leader motor to zero (0). Adjust the “MIN” trimpot so
that the output at terminals “ ” and “10” reads zero (0) volts.
c) Reset the armature voltage of the leader motor to 0V. Adjust the “MAX” trimpot so
that the output voltage is V DC.
Notes:
1. When setting the output voltage using the “MIN” and “MAX” trimpots the voltage or speed
of the driven motor can be read directly instead of using the output of the BC145.
2. When readjusting the “MIN” and “MAX” trimpots, always set the minimum voltage first and
then the maximum voltage.
3. Trimpots allow approximately 20 turns for the full range of adjustment. If during the adjust-
ment procedure the output stops changing, try reversing the direction of rotation of trimpot.
IV. OUTPUT SIGNAL
The output signal from the BC145 is obtained from terminals “ ” (-) and “10” (+). Connect the
output directly to the signal following input terminal of the speed control. For multiple follower
motors, several controls can be driven from a single BC145. Be sure the AC line connections
to the follower control are to the same phase (eg, L1 to L1 and L2 to L2 of all controls.)
The output from the BC145 can be scaled to control the speed control over any desired speed
range. Adjust the “MIN” trimpot to provide the desired minimum speed and the “MAX” trimpot
to provide the desired maximum speed.
8

Isolation Diode
F(–)
A(–)
A(–)
A(+)
A(+)
Additional
Slaves
Follower
Motor #1
Follower
Motor #2
Follower
Motor #3
A(–)
A(+)
P2
F(–)
P2
F(–)
P2
Ratio 5KΩ
(–)
10(+)
BC145
5
7
Leader Motor
A(–)
A(+)
BC141 BC141
BC141
BC141
FIGURE 5 – LEADER/FOLLOWER VOLTAGE FOLLOWING SYSTEM WITH MULTIPLE MOTORS
A) From a Single Main Motor
BC145
6
10 (+)
(–)
P1*
5K
Pot
5
*Connect high side of potentiometer
to terminal "P1" (1/4" QD)
Connect
as above
WARNING! If Signal Isolator is connected to multiple speed controls;
1) Multiple controls must be powered from the same phase of AC line.
2) The positive input terminal to each speed control must be installed with a 1 amp - 600V isolation diode as
shown.
3) Multiple speed controls can not be used with PWM, Regenerative or Adjustable Frequency Drives (Inverters).
B) From a Single Main Potentiometer
A 10K ratio poten-
tiometer is used to
control up to ten (10)
follower motors.
If a 5K ratio poten-
tiometer is used, up
to five (5) follower
motors can be con-
trolled.

10
Motor
A(–)
F(–)
A(+)
P3
5K Pot
Auto/Man
10(+)
(–)
Manual
5K Speed Pot
P2
P1 CONTROL
BC145
The BC145 can be
wired in an
Auto/Manual mode
which will allow
manual override of
an automatic
process. See figure
6B.
FIGURE 6B – PROCESS CONTROL WITH AUTO/MANUAL SWITCH
9(–)
10(+)
BC145
5
7
90V DC
Leader Motor
A(–)
A(+)
BC141 BC141
Speed
Pot
AC Line AC Line AC Line
F-
Follower
Motor #1
A(–)
A(+)
P2 L1 L2
FIGURE 6A – LEADER/FOLLOWER VOLTAGE FOLLOWING SYSTEM

Note: The preceding circuit provides for the speed pot to be used in “MAN” mode only. In “AUT0”
mode, the process control signal is supplied directly to the signal isolator.
11
Motor
A(–)
F(–)
A(+)
P3
Auto
W/Ratio Manual
5K Pot
10(+)
(–)
P2 CONTROL
BC145
The following circuit
provides for dual pur-
pose usage of the
speed pot. In the
“AUTO” mode it is
used for ratio control
and in the “MAN”
mode it is used for
manual speed adjust-
ment.
FIGURE 6C – PROCESS CONTROL WITH AUTO (RATIO POT)/MANUAL SWITCH
Motor
F(–)
P2
A(–)
A(+)
9(–)
10(+)
5
6
P1
Auto/Man 5K Pot
CONTROL
Process
Signal
0 - 10V DC
BC145
FIGURE 6D – AUTO/MANUAL OPERATION WITH POTENTIOMETER ON BC145 INPUT

(A42086) – Rev. B – 7/2000
V. LIMITED WARRANTY
For a period of 2 years from date of original purchase, BALDOR will repair or replace without charge
controls which our examination proves to be defective in material or workmanship. This warranty is
valid if the unit has not been tampered with by unauthorized persons, misused, abused, or improperly
installed and has been used in accordance with the instructions and/or ratings supplied. This warran-
ty is in lieu of any other warranty or guarantee expressed or implied. BALDOR shall not be held
responsible for any expense (including installation and removal), inconvenience, or consequential
damage, including injury to any person, caused by items of our manufacture or sale. (Some states do
not allow the exclusion or limitation of incidental or consequential damages, so the above exclusion
may not apply.) In any event, BALDOR’s total liability, under all circumstances, shall not exceed the
full purchase price of the control. Claims for purchase price refunds, repairs, or replacements must be
referred to BALDOR with all pertinent data as to the defect, the date purchased, the task performed by
the control, and the problem encountered. No liability is assumed for expendable items such as fuses.
Goods may be returned only with written notification including a BALDOR Return Authorization
Number and any return shipments must be prepaid.
Baldor Ele tri Company
5711 R. S. Boreham, Jr. Street
Fort Smith, AR 72 02-2400 U.S.A
(501) 646-4711 Fax (501) 648-57 2
International Fax (501) 648-58 5
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