Wesley BC-620-4CA User Manual
Page 23
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Curtis 1234/36/38 Manual,
OS
11
19
2 3 J U LY 2 0 0 8 D R A F T
1236/38
*
→
1234
*
→
Low power outputs
Two control lines on the 1236/38 are available as low power digital outputs.
These are open collector drivers that can only sink current, not source it, and
are intended to drive LEDs or other low current loads connected to the +5V
or +12V external power supplies; see power supply output group specs. Fault
protection will turn off these outputs if output voltage exceeds about 15 V
when the output is On (low output). Both outputs are protected against shorts
to B+ or B-.
These lines can also be used as digital inputs, and are included in that
group as well.
2 — INSTALLATION & WIRING:
I/O Signal Specifications
LOW POWER OUTPUT SPECIFICATIONS
ALLOWED
OUTPUT
PROTECTED
ESD
SIGNAL
NAME
PIN
VOLTAGE
IMPEDANCE
VOLTAGE
TOLERANCE
Digital Out 6
19
0 to 15 V
On: 1 kΩ to B-
- 5 V to
± 8 kV (air
Digital Out 7
20
Off: 134 kΩ
(MaxV + 10 V) discharge)
*
The digital outputs for the 1234 are below, with the high power outputs
.
High power outputs
Seven control lines on the 1234 and five on the 1236/38 can be used as high
power output drivers. One of these, the proportional driver, can be operated in
a current control mode for driving a proportional valve or similar load. Each
output can be independently turned on continuously (low level) or pulse width
modulated to set the average output voltage. These outputs are intended to
drive inductive loads such as contactors and electromagnetic brakes but could
also be used to drive resistive loads if peak current ratings are not exceeded. All
these outputs are protected against shorts to B+ or B-.
These lines can also be used as digital inputs, and are included in that
group as well.
HIGH POWER OUTPUT SPECIFICATIONS
PV
FREQ
-
OUTPUT
PROTECTED
ESD
SIGNAL
NAME
PIN
PWM
CURRENT
UENCY
CURRENT
VOLTAGE
TOLERANCE
Driver 1
6
0 to 100% n/a
200 Hz 2 A max - 0.5 V to
± 8 kV (air
Driver 2
5
duty cycle
3 A max keyswitch discharge)
Driver 3
4
2 A max voltage
Driver 4
3
Prop Driver 2
0 to 2 A 18 kHz
in 607
nominal
steps
Digital Out 6 19
on/off
n/a
n/a 1 A max
Digital Out 7 20
*
On the 1234, the combined current supplied
by all seven output drivers should not exceed 10 A
.