PT8CN
CANbus • SAE J1939 Output Signal
Industrial Grade String Pot
Absolute Linear Position to 60 inches (1524 mm)
Aluminum or Stainless Steel Enclosure Options
NEMA 6 / IP67
GENERAL
Full Stroke Ranges
0-2 to 0-60 inches
Electrical Interface
CANbus SAE J1939
Protocol
Proprietary B
Accuracy
see ordering information
Repeatability
± 0.02% full stroke
Resolution
± 0.003% full stroke
Measuring Cable Options
Enclosure Material
Sensor
stainless steel or thermoplastic
powder-painted aluminum or stainless steel
plastic-hybrid precision potentiometer
Potentiometer Cycle Life
see ordering information
Maximum Retraction Acceleration
see ordering information
Weight, Aluminum (Stainless Steel) Enclosure
3 lbs. (6 lbs.), max.
ELECTRICAL
Input Voltage
7 - 18 VDC
Input Current
60 mA max.
Baud Rate
Update Rate
125K, 250K, or 500K via DIP switches
10 ms. (20 ms. available, contact factory)
3.6” [91 mm]
5.6” [141 mm]
The PT8CN, using a high cycle plastic-hybrid potentiometer,
communicates to your PLC via the CANbus SAE J1939 interface. Suitable for factory and harsh environment applications requiring linear position feedback in ranges up to 60”.
As a member of Celesco’s innovative family of NEMA 4 rated
cable-extension transducers, the PT8CN installs in minutes
by simply mounting it’s body to a fixed surface and attaching it’s cable to the movable object. Perfect parallel alignment not required.
ENVIRONMENTAL
Environmental Suitability
NEMA 4X/6, IP 67
Operating Temperature
Vibration
-40° to 185°F (-40° to 85°C)
up to 10 g to 2000 Hz maximum
Output Signal:
data stream
{ 0000x0 ...
(0% fs.)
... FFFFx0
}
(100% fs.)
20630 Plummer Street • Chatsworth, CA 91311
tel: 800.423.5483 • +1.818.701.2750 • fax: +1.818.701.2799
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PT8CN | 1
1 bit
29 bits
0-8 bytes
1 bit 6 bits
15 bits
ace
Inte
rfram
e Sp
Fram
e
er
1 bit 1 bit 1 bit
End
of
Ack
Delim
it
CRC
Delim
iter
Ack
Slot
CRC
Sequ
ence
Data
Field
Cont
rol F
ield
r
RTR
Bit
Iden
tifie
Inte
rfram
e Sp
ace
Start
of Fr
ame
I/O Format and Settings
7 bits
3 bits
repetition = 8 msec.
• Identifier
Example –
1
0
0
Identifier Bit No. –
28
27
26
J1939 Reference
Proprietary B
Future
Use
Message Priority
0
0
1
1
25
24
23
22
0
Hex Value –
1
1
1
1
21
20
19
18
F
Data Field Type*
1
1
0
1
17
16
15
14
F
0
1
0
0
13
12
11
10
5
Not Used
1
1
0
0
9
8
7
6
3
Velocity Data
B0 = LSB current % of measurement range byte
B1 = MSB current % of measurement range byte
B4 = error flag
B5 = error flag
B2 = LSB current measurement count byte
B3 = MSB current measurement count byte
B6 = LSB velocity data byte
B7 = MSB velocity data byte
B5
B4
B3
B2
B1
B0
B7
B6
B5
1
1
5
4
3
2
3
• Data Field
B6
1
1
1
1
0
F
**Customer defined, set via Dips 1-6. Bit values shown for example only, see Address Setting below.
*Sensor field data can be factory set to customer specific value.
B7
Node ID**
1
B4
B3
B7
B2
B1
B6
Error Flags
B5
B4
B7
B0
B6
Current
Measurement
Count
Current % of
Measurement
Range
B3
B1
B5
B2
B4
B3
B2
B1
B0
B0
Current Measurement Count
Current % of Measurement Range
Velocity
The Current Measurement Count (CMC) is the output
data that indicates the present position of the
measuring cable. The CMC is a 16-bit value that
occupies bytes B2 and B3 of the data field. B2 is
the LSB (least significant byte) and B3 is the MSB
(most significant byte).
The Current % of Measurement Range is a 2-byte
value that expresses the current linear position as a
percentage of the entire full stroke range. Resolution
is .1 % of the full stroke measurement range.
Data in bytes B7 - B6 is the change in the CMC
(current measurement count) over a 100 msec time
period. This data can then be used to calculate
velocity in a post processing operation.
The CMC starts at 0x0000 with the measuring cable
fully retracted and continues upward to the end of
the stroke range stopping at 0xFFFF. This holds
true for all ranges.
This value starts at 0x0000 at the beginning of the
stroke and ends at 0x03E8.
(
65,535
)
full stroke
X
range
If the full stroke range is 30 inches and the current
position is 0x0FF2 (4082 Decimal) then,
(
65,535
)
X 30.00 inches
=
1.87 inches
If the full stroke range is 625 mm and the current
position is 0x0FF2 (4082 Decimal) then,
(
4082
65,535
Percent
0.0%
0.1%
0.2%
...
100.0%
)
X 625 mm = 39 mm
0x7FFF (32767)
“0” counts
(no change)
0xFFFF (65535)
32767 counts
Velocity Calculation
(
B7
B6
B5
B4
B3
B2
B1
count change – 32767
.1 sec. time period
) (
X
full stroke range
65,535
)
B0
Error Flags
Sample Conversion:
4082
Decimal
0000
0001
0002
...
1000
Velocity
(cts./100 msec.)
– 32767 counts
0x0000 (0)
Hex
0000
0001
0002
...
03E8
To convert the current measurment count to inches
or millimeters, simply divide the count by 65,535
(total counts over the range) and then multiply
that value by the full stroke range:
current measurement
count
HEX (Decimal)
Example:
Converting CMC to Linear Measurement
max
max
“reverse” “forward”
velocity velocity
B7 - B6
0x55 (yellow LED on controller board) indicates that
the sensor has begun to travel beyond the calibrated
range of the internal position potentiometer.
0xAA (red LED on controller board) indicates that
the sensor has moved well beyond the calibrated
range of the internal position potentiometer.
If either error flag occurs within the full stroke range
of the sensor, the unit should be returned to the
factory for repair and recalibration.
Sample Calculations
Cable Extension (positive direction):
B7–B6 = 0x89C6 (43462 Dec), full stroke = 60 in.
(
35270- 32767
.1 sec
) (
X
60 in.
65,535
)=
22.92 in. / sec.
Cable Retraction (negative direction):
B7–B6 = 0x61A8 (25000 Dec), full stroke = 60 in.
(
25000– 32767
.1 sec
) (
X
60 in.
65,535
)=
– 71.11 in. / sec.
tel: 800.423.5483 • +1.818.701.2750 • fax: +1.818.701.2799
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2 | PT8CN
Setting the Address (Node ID) and Baud Rate
Address Setting (Node ID)
Baud Rate
The Address Setting (Node ID) is set via 6
switches located on the 8-pole DIP switch
found on the DeviceNET controller board
located inside the transducer.
The transmission baud rate may be either factory
preset at the time of order or set manually at the
time of installation.
DIP-2
0
1
0
...
1
(20)
(21)
DIP-3 DIP-4
The baud rate can be set using switches 7 & 8 on
the 8-pole DIP switch found on the DeviceNET
controller board located inside the transducer.
DIP-5
DIP-6
0
0
0
...
0
0
0
...
0
0
0
...
address
(decimal)
0
1
2
...
1
1
1
63
(22)
(23)
0
0
1
...
0
0
0
...
1
1
(24)
address / baud rate switches
1 2 3 4 5 6 7 8
The DIP switch settings are binary starting
with switch number 1 (= 20) and ending
with switch number 6 (= 25).
DIP-1
CANBus Controller Board
(25)
DIP-7
0
1
0
1
DIP-8
0
0
1
1
baud rate
125k
250k
500k
125k
internal dip switches
& controller board
= "0"
1 2 3 4 5 6 7 8
= "1"
to gain access to the controller board, remove four
Allen-Head Screws and remove rear cover.
Outline Drawing:
see eyelet detail
A
0.99 [25,1]
eyelet detail
Ø.191 [4,19]*
Ø.375 [9,52]**
.165 [4,19]**
1.80 [45,7]
0.08 [2,0]
3.50 [88,9]
2.49 [63,3]
1.50 [37,6]
1.30 [33,3]
3.60 [91,4]
RANGE
2”, 10”
5”, 25”, 50”
15”
20”, 40”
30”, 60”
0.60 [15,2]
5.56 [141,2] max.
A
1.16 [29,5]
0.66 [16,8]
0.99 [25,7]
0.85 [21,6]
0.52 [13,3]
DIMENSIONS ARE IN INCHES [MM]
tolerances are ±0.02 in. [±0,5 mm] unless otherwise noted
note: *tolerance = +.005 –.001 [+.13 –.03]
3.00 [76,2]
Ø.27 [6,8] thru
(4 places)
1.64 [41,6]
**tolerance = +.005 –.005 [+.13 –.13]
tel: 800.423.5483 • +1.818.701.2750 • fax: +1.818.701.2799
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PT8CN | 3
Ordering Information:
Model Number:
Sample Model Number:
PT8CN - 50 - AL - N34 - T1 - CG - J - 500 - 32 - SC5
PT8CN order code:
Full Stroke Range:
R order code:
full stroke range, min:
accuracy (% of f.s.):
potentiometer cycle life*:
R
-
A
-
B
-
C
-
D
J
-
E
-
F
-
G
-
R
A
B
C
D
E
F
G
H
H
range:
enclosure
measuring cable:
measuring cable tension:
cable guide:
interface:
baud rate:
node ID:
electrical connection:
50 inches
aluminum
.034 nylon-coated stainless
standard
standard
CANbus SAE J1939
500 k bits/sec.
32 decimal
5-meter cordset with straight plug
2
5
10
15
20
25
30
40
50
60
2 in.
0.25%
5 in.
0.25%
20 in.
0.15%
5 x 105
25 in.
0.15%
5 x 105
30 in.
0.15%
5 x 105
50
0.10%
60
0.10%
2.5 x 106
15 in.
0.15%
5 x 105
40 in.
0.10%
2.5 x 106
10 in.
0.15%
5 x 105
2.5 x 105
2.5 x 105
2.5 x 105
*–1 cycle is defined as the travel of the measuring cable from full retraction to full extension and back to full retraction
Enclosure Material:
AL
SS
316
powder-painted aluminum
303 stainless steel
316 stainless steel
A order code:
Measuring Cable:
B order code:
N34
S47
S31
V62
cable construction:
Ø.034-inch nylon-coated
stainless steel rope
Ø.047-inch bare
stainless steel rope
Ø.031-inch bare
stainless steel rope
Ø.058-inch PVC jacketed
vectra fiber rope
all ranges
5, 15, 20, 25, 30-inch only
40, 50, 60-inch only
thru 30 inches only
indoor
outdoor, debris,
high temperature
outdoor, debris,
high temperature
high voltage or
magnetic field
available ranges:
general use:
Measuring Cable Tension:
T1
T2
T3
standard tension
39 oz.
26 oz.
20 oz.
16 oz.
13 oz.
medium tension
65 oz.
43 oz.
33 oz.
26 oz.
22 oz.
high tension
116 oz.
77 oz.
60 oz.
47 oz.
40 oz.
C order code:
2, 10-inch:
15-inch:
20, 40-inch:
5, 25, 50-inch:
30, 60-inch:
full stroke range
cable tension
specifications
tension tolerance: ± 50%
maximum acceleration
aluminum enclosure:
stainless steel enclosure:
maximum acceleration
15 g
6g
Cable Guide:
maximum acceleration
25 g
12 g
40 g
18 g
standard cable guide
stainless steel cable guide
polyurethane cable guide
1.87 in.
BR
integral cable brush
1.88 in.
CB*
3.75 in.
SS
1.87 in.
CG
D order code:
*note: all ranges up to 25 inches only
tel: 800.423.5483 • +1.818.701.2750 • fax: +1.818.701.2799
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4 | PT8CN
Ordering Information (cont.):
Baud Rate:
125
250
500
125 kbaud
250 kbaud
500 kbaud
F order code:
Node ID:
0
G order code:
1
2
...
62
63
select address (0 - 63 Decimal)
Electrical Connection:
blank
MC5
SC5
NC5
5-pin micro-connector
(no mating plug supplied)
5-pin micro-connector
w/ mating plug
5-pin micro-connector
and 5 meter length cordset
w/straight mating plug
5-pin micro-connector
and 5 meter length cordset
w/90º mating plug
H order code:
#2 V+
#3 V–
#1 Drain
#5 CAN-L
#4 CAN-H
connector
(contact view)
0.16" - 0.32" OD Cable (THIN)
length: 16ft [5M]
cable: Thin
2
mating plug
(contact view)
1
5
4
pin
1
2
3 3
4
5
signal
drain
V+
VCan-H
Can-L
length: 16ft [5M]
cable: Thin
wire color
brown
white
blue
black
grey
version: 10.0 last updated: May 29, 2014
tel: 800.423.5483 • +1.818.701.2750 • fax: +1.818.701.2799
meas-spec.com
PT8CN | 5