Precision Digital Corporation Trident PD765, Инструкция по эксплуатации

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Trident Series PD765 Process & Temperature Meters
Instruction Manual
9
Relays Option
Rating
2 Form C (SPDT); rated 3 A @ 30 VDC
or 3 A @ 250 VAC resistive load;
1/14 HP (≈ 50 watts) @ 125/250 VAC
for inductive loads such as contactors,
solenoids, etc.
Deadband
0-100% FS, user selectable
Electrical Noise
Suppression
A snubber should be connected to
each relay contact switching inductive
loads to prevent disruption to the
microprocessor’s operation.
Recommended snubber value:
0.01 µF/470 Ω , 250 VAC ( PDX6901 ).
High or Low
Alarm
User may program any alarm for high
or low
Relay
Operation
•
Automatic (non-latching) and/or
manual reset
• Latching (requires manual
acknowledge) with/without clear
•
Pump alternation control
• Off (disable unused relays)
Relay Reset Front panel button, terminal at back of
meter (X2 models only), or through
serial communications
Time Delay 0 to 199 seconds, on and off delays;
programmable
Sensor Break
Relay Operation
The sensor break relay condition may
be programmed for each relay as
On (alarm) or Off (nonalarm).
The relays will enter these states when
a sensor break is detected for RTD or
thermocouple inputs. These settings
have no effect when current or voltage
inputs are selected.
Fail-Safe
Operation
Programmable, independent for each
relay. Relay coils are energized in
non-alarm condition. In case of power
failure, relays will go to alarm state.
Auto
Initialization
When power is applied to the meter,
relays will reflect the state of the input
to the meter.
Serial Communications
Compatibility
EIA-232, and EIA-485 with PDA7232
and PDA7422 Trident adapters.
Protocol Modbus RTU
Meter
Address
PDC protocol: 0 - 99
Modbus protocol: 1 - 247
Baud Rate 300 – 19,200 bps
Transmit
Time Delay
Programmable 0 to 199 ms
Data 8 bit (1 start bit, 1 stop bit)
Parity
None (1 or 2 stop bits), even, or odd
(Modbus only; PDC protocol does not
use parity)
Turn Around
Delay
Less than 2 ms (fixed)
Refer to PDC and Modbus Serial Communication
Protocol manuals for details.
Isolated 4-20 mA Transmitter
Output
Scaling Range 1.00 to 23.00 mA; reverse scaling
allowed.
Calibration Factory calibrated for 4-20 mA
Accuracy ±0.1% FS ±0.004 mA
Temperature Drift 50 PPM/°C
Note: Analog output drift is separate
from input drift.
Isolation
500 V input-to-output or output-to-24
VDC supplies; 4 kV output-to-power
line. For -6X5 models only:
100 V output-to-24 VDC supply
External Power 35 VDC maximum
Output Loop
Resistance
Power
supply
Minimum Maximum
24 VDC
10 Ω 700 Ω
35 VDC
(external)
100
Ω
1200
Ω
Additional 4-20
mA Outputs
The PD659-1MA-2MA can split the
optional 4-20 mA output into two
isolated 4-20 mA outputs
0-10 VDC Output The PD659-1MA-1V can convert the
optional 4-20 mA output to a 0-10 VDC
signal
External Button Contacts
(X2 Models Only)
Number
Four
Function Remote operation of front-panel
buttons: programming, reset relays or
view/reset max/min readings.
Open State +5 VDC open contact on button input
terminals
Closed State
Closed contact button input terminal to
common/ground, active low 0 to 0.4 VDC