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Curtis 1356/1356P CAN Expansion Module Manual,
Rev. A
Driver Outputs
The 1356 /1356P contains two driver outputs. These outputs have all the
features necessary to drive proportional valves as well as many other inductive
and non-inductive loads. A variable amount of dither (fixed frequency com-
mand “jitter”) can be added to the PWM to prevent proportional valves from
sticking in place.
2 — INSTALLATION & WIRING:
I/O Signal Specifications
DIGITAL OUTPUT SPECIFICATIONS
signal
name
pin
max
current
impedance
frequency
Input/Output 1 J1-2
3 A
12 – 36V models:
All models:
10 kΩ pulldown to B-
16 kHz
Input/Output 2 J1-14
1 A
36 – 80V models:
0–100% duty cycle
47 kΩ pulldown to B-
The drivers can be set for Constant Current, Constant Voltage, or Direct PWM
control mode.
In Constant Current mode, the driver command of 0 to 100%
is interpreted as a current from 0 to the Max Output setting.
Internal current shunts are measured and fed back to a closed
loop PI controller to provide a steady current over changing
loads and supply voltages.
In Constant Voltage mode, the driver command of 0 to 100%
is interpreted as a voltage from 0 to Max Output. The battery
voltage is constantly monitored and fed back to a closed loop
PI controller to provide a steady voltage, compensating for
battery droop and discharge. If the command is higher than
the driver can output, the PWM will max out at 100%.
In Direct PWM mode, the driver command of 0 to 100% is
directly output on the driver.
Each driver is monitored and will detect a short in the load, a failed internal
driver FET, and/or an open in the load wiring. At near 0% and 100% PWM,
it is not possible to discern each fault and some faults will not be detected.
If the driver outputs are connected to inductive loads, the coil should
have a return line to the B+ pin of the 1356 /1356P. This connection provides
a path for the internal freewheel diodes to clamp the turn-off spike. Failure
to make this connection with inductive loads can cause permanent damage to
the 1356 /1356P as well as propagate failures of other electronics in the system
due to the high voltage spike caused when an inductive load turns off without
a freewheel path.
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Summary of Contents for 1356
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