BusWorks® Model 989EN U
ser’s Manual Modbus TCP/IP Digital I/O & Counters
_________________________________________________________________________________
_______________________________________________________________________________________
Acromag, Inc. Tel:248-295-0880 Fax:248-624-9234 Email:
58
Input Timer Accuracy:
Frequency
≥ 1 Hz Frequency < 1 Hz
≤ ±1 ms
±0.1% or better
Output “OFF” Voltage Range:
0 to 28V DC, 31V maximum. Output
control voltage range is first limited to 28V or the excitation voltage
level, whichever is less, then the transient voltage suppression (31V,
see below), then the input circuitry (38V), then the output driver (50V).
Built-in over-voltage protection limits the output operating range (see
below) and may temporarily shut the output down for excitation voltages
greater than 28V, or output drain-source voltages greater than 50V.
Output Drain-to-Source ON Resistance (Rds):
0.55
Ω typical (25°C), 1.1Ω
maximum (125°C junction temperature).
Output “ON” Current Range:
1mA to 500mA maximum DC continuous,
each output. The sixteen outputs share 3 common return terminals
(RTN) which are limited to 2A combined total (giving 0.125A /16ch or
0.5A/4ch). No deration is required at elevated ambient temperature.
Individual outputs also have internal over-current fault limits of 1.2A
typical (0.9A to 2.5A range) that will limit current until the internal over-
temperature limit is reached, triggering a thermal shutdown of the
output (see below). Note the input wetting current is additive to the load
current (2mA/16mA), but may be optionally turned off (with inputs tri-
stated).
Output “OFF” Leakage Current:
10uA typical, 20uA maximum. This
increases by 50uA if open-load detection is enabled.
Output Excitation:
Excitation is connected between the Exc and Return
terminals and must be a DC voltage from 8 to 28V DC. Inputs and
outputs will not operate without excitation. The excitation input includes
transient protection and filtering, plus a series connected reverse
polarity blocking diode. The port input wetting current and internal logic
currents are all sourced from the excitation supply.
Output Over-Voltage Protection:
Outputs are intended to switch voltages
within the excitation voltage range, but will shutdown operation for
excitation over-voltage conditions above 28V (30V typical, 35V max),
and any drain-to-source voltages greater than 50V. Normal operation
will resume following shutdown upon return to proper voltage level.
Note that sustained voltages above 31V can damage the transient
voltage suppressor. Following a fault shutdown, the outputs may be
configured to retry the previous state, or remain OFF, depending on the
settings of the Output Global Shutdown/Retry Control register.
Output Over-Current Protection:
The outputs have internal self-limiting
ON state currents of 1.2A typical (0.9A to 2.5A range). An output will
limit fault current in this range until the output thermal limit is reached
and the output enters over-temperature shutdown. A thermal fault flag
will be set. Only the faulted output will shut-down, not every outputs.
Upon removal of the fault condition, the output will automatically return
to its previous state, or stay OFF, based upon the control bit settings in
the Output Global Shutdown/Retry Control Register.
WARNING:
Individual output current is limited to 500mA maximum.
You should not attempt to operate outputs above these limits or you
may exceed the safe operating range for the foils of the circuit board,
which may result in permanent damage to the unit.
SPECIFICATIONS
Digital Inputs
Digital Outputs
IMPORTANT:
Inputs and
Outputs will not operate
without excitation.
To control higher voltages
and/or currents, or for
controlling AC, an interposing
relay may be used.
