CSI PWM-C1 Assembly instructions

PWM-CPulseWidthModulation to
Current Transducers
Control Systems
International
®
General
CSI’s Model PWM-C1 and PWM-C2 transducers provide a 4 to
20 mA and 0 to 20 mA output,respectively,proportional to the
duration of the pulse input.
Both the PWM-C1 and PWM-C2 are provided with a simple 3-
wire electrical connection for control,and 2-wire electrical
connection to the controlled device.
Physical Description
ThePWM-C1andPWM-C2arecontainedonasingleintegrated
circuit board with a footprint of 3.25"W × 4.0" H (8.25 ×
10.2 cm),and are designed for panel mounting using the snap-
track mounting rail. Overall mounting dimensions,including
snap track rail, are 3.5"W ×
4.0" H (8.9 × 10.2 cm).
Electrical connections are terminated on a 5-position terminal
strip on the bottom edge of the card for easy access.
PowerandclockstatusisdisplayedviaagreenLED.Thepresence
of a PWM signal from the controller is indicated by a red LED.
ThePWM-Ctransducersmaybepoweredbya24-voltACorDC
source to eliminate the requirement for a special transformer or
power supply for a single transducer.Controller pulse inputs
may be created by mechanical dry contacts,solid state open
collector transistors (NPN), or triacs as shown in the wiring
diagram.
Note: If the controller output providing the pulse width signal
is a UC triac, you must remove resistor R-27 and diode
D-5 as shown in the wiring diagram. If the controller is
an MR or I/SITE I/O triac, only remove R-27.
PWM-C transducers input full range time is user-selectable
between two jumper selectable ranges: 0.1 to 5.2 second pulse
input or 0.1 to 25.6 second pulse input,to provide rapid loop
response time when required.
•
The time base is jumper selectable via a plug-on jumper
labeled J2.
•
An input pulse of less than 0.1-second duration will be
rejected by the transducer and no change will occur in the
output.
The PWM-C transducers internally limit the maximum input
signal to a full scale range of 255 counts,and do not allow wrap-
around on pulses of longer duration than the specified or
selected maximum.
Upon power initialization,the PWM-C transducers force the
output to 0% of scale value until receipt of the first pulse input
from the controller.
Installation Instructions/Precautions
1.
Carefully remove the PWM-C transducer from the anti-
static packing material.
2. Withduecaution,removethetransducerassemblyfromthe
snap track.
Note: Until you are ready to finally mount the transducer in the
snap track it is recommended that the transducer be
replaced in the anti-static packaging to prevent damage.
3. Mount the snap track in the desired location,making sure
thatthescrewsusedtomountthesnap-trackdonotcontact
the underside of the transducer.
a. Thetransducermaybemounted eitherhorizontally or
vertically without affecting the operation of the unit.
b. If mounted vertically, you must install a stop at the
bottom edge of the snap-track to prevent vibration
fromcausing thetransducertomigrate outof the snap-
track.
4. Make all electrical connections with power Off.

PWM-C Transducers Installation Sheet TCON172 06/97
P.O.Box 59469,Dallas,TX 75229
Phone: [phone] FAX: [phone]
 1997 by Control Systems International.
Control Systems
International
®
Specifications
Dimensions................................................... 3.25" W × 4.0" L
...................................................................(8.25 × 10.2 cm)
Snap-track dimensions.................................. 3.5" W × 4.0 " L
.....................................................................(8.9 × 10.2 cm)
Input pulse duration................................... 0.1–25.6 seconds
or................................................................ 0.1–5.2 seconds
Input pulse resolution.....................................................0.4%
Resolution counts.......................................................... 0–255
Input interface
...................Dry contact,triac or open collector transistor
Input excitation voltage............................................+15VDC
........................................................(continuous or pulsed)
Output current range:
PWM-C1............................................................... 4–20 mA
PWM-C2............................................................... 0–20 mA
Output excitation voltage........................................13.5VDC
.....................................(675 Ω maximum loop resistance)
Linearity.............................................................. 1% full scale
Operating temperature.......................... 32–132 ° F (0–50 ° C)
Relative humidity..........................10–90% (noncondensing)
Supply voltage.......................................24–35VDC @ 75 mA
or .....................................18–28 VAC @ 150 mA, 50/60 Hz
Engineering Coefficients (input range 0.1–5.2 seconds):
M (slope).................................................................0.19608
B (intercept)...........................................................-1.96078
Engineering coefficients (input range 0.1–25.6 seconds):
M (slope).................................................................0.03922
B (intercept)...........................................................-0.39216
Note: These M and B coefficients apply to 0–100% input source
range.
Figure 1. PWM-C Series Wiring Diagram
Remove both R27 and
Input
Power
Clock
3.5" Width
4.0" Length
J25
Sec Sec
25
R27 D5
Red LED Indicates Detection
Of Pulse Input
Green Flashing LED indicates
Power and Clock Rate
5 Sec/25 Sec
Pulse Width
Selection
Remove R27 for MR
or I/SITE triac input.
– Common (Ground)
+ Current Output to
+24 V
–GND
24V Supply
Polarity
Indication
Applies if DC
Supply Is Used
Common (Ground)
Connection When
Triac or Transistor
Output Is Used
Pulse Width
Modulated
Output Using
Normally-Open
Relay Contact
or
Open Collector
Transistor
or Triac
CONTROLUNIT
Device Under Control
D5 for UC triac input.
1
V2 G3
I4
O5 G
0.47 µf
Install 0.47 µf capacitor
across terminals 2 and 3
if used with MR-VAV-AX.
1
V2 G3
I4
O5 G