Precision Digital

PDS178 Watchdog Scanner Temperature & Process System

Combination of the Trident meter, the Minimux II scanner, and the PDA2821 NEMA 4X enclosure, automatically switches between up to eight input signals

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$822.00 CAD
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The PDS178 Watchdog Temperature Scanning & Alarming System brings together a popular combination of Precision Digital products: the Trident meter, the Minimux II scanner, and the PDA2821 NEMA 4X enclosure. The scanner automatically switches between up to eight (8) input signals (4-20 ma, ±10 V, TC, or RTD) and sends them to the Trident meter for display. Signal switching is done via DPST reed relays. The Watchdog can be used in a variety of temperature and process monitoring applications. A very common application for this system is to monitor bearing temperatures. The Trident meter included with this system is available with standard 0.56" (14.2 mm) high LED digits or large 1.2" (30.5 mm) high LEDs.

Trident Temperature & Process Meter
• 4-20 ma, ±10 V, TC & RTD Inputs
• 4-Digit Red LEF Display
• Two Relays for Alarm Signal to PD138
• NEMA 4X, IP65 Front
• Sunlight Readable Display

Minimux II Temperature/Process Scanner
• 8 Inputs per Unit
• Thermocouples, RTDs, and Process inputs
• Adjustable Dwell Time for Each Channel
• Independent Alarm Input for Each Channel
• First-Out Alarm Indication
• Alarms Indicated by LEDs, Built-in Horn, and Relay
• Built-in 85 dB Horn with Silence Pushbutton
• Stop-on-Alarmed Channel (Field Select)
• Sunlight Readable Indication
• NEMA 4X/IP65 Front

Plastic NEMA 4X Enclosure
• NEMA 1, 4, 4X, 6, 12, and 13, IP66
• Wall Mountable

Weight 9.5 oz (269 g) (including options)
Enclosure 1/8 DIN, high impact plastic, 94V-0, color; gray
Colour Grey
Display Trident: 0.56 (14.2 mm) red LED, 4 digits (-1999 to 9999)
Trident X2: 1.20 (30.5 mm) red LED, 4 digits (-1999 to 9999)
No. Of Channels 8 double-pole channels per unit
No. Of Channels Per System Unlimited
Signals Switching DPST reed relays
Contact Resistance 0.2 Ω maximum
Maximum Input Voltage 200 V (switched or common mode)
Maximum Current Switched 0.5 A
Maximum Power Switched 10 W
Dwell Time Each channel adjustable from 0.6 to 30 seconds
Non-Volatile Memory All programming values are stored in non-volatile memory for ten years if power is lost
Scan Method Internal or manually controlled
Channel Indication Green LED on front panel
Disabling Channels Any channel may be disabled during setup
Scan Stop The scan may be stopped by pressing and holding the STOP/GO button for more than 0.5 seconds. The scan may be resumed by pressing and releasing the STOP/GO button quickly (less than 0.5 seconds)
Alarm Input Independent alarm input for each channel. Input Impedance; 25 K Ω, typical pull-up to 5 V
Alarm Sequence Sequence A or Sequence F2A (first out)
Alarm Outputs Alarm condition indicated by:
1. Front panel red LED for each channel
2. Relay, 1 SPDT (form C); rated 2 Amp @ 30 VDC or 2 Amp 2. @ 250 VAC resistive load; 1/14 HP @ 125 / 250 VAC for inductive loads. For fail-safe operation, the relay is energized in the non-alarm state. In the case of a power failure, the relay will go to the alarm state, (NC contact is connected to common)
3. Built-in Horn, 85 dB
4. Stop-on-alarmed-channel (user select)
Alarm Acknowledge Front panel ACK and rear connector terminals
External Switch Functions The functions of the front panel buttons are available at screw terminals at the rear of the instrument
Message Labels Free, custom printed, 2 lines per message at 14 characters per line. Factory or field printable. See manual for details
Connections Power & Signal: removable screw terminal blocks accept 12 to 22 AWG.
Serial: RJ11 header, standard on all meters.
Operating Temperature -40C to 65C
Storage Temperature -40C to 85C
Relative Humidity 0 to 95% non-condensing
Power Options 115 VAC, 10%, 50/60 Hz, 4 VA; 230 VAC, 10%, 50/60 Hz, 4 VA; 12-24 VDC (9-18 VAC, 50/60 Hz) 2 W
Led Test All LEDs are tested on power-up
Enclosure 1/8 DIN, high impact plastic, UL94V-0
Front Panel NEMA 4X, panel gasket provided
Warranty 3 years parts & labor
Display Intensity Eight user selectable intensity levels
Front Panel NEMA 4X, IP65; panel gasket provided
Programming Methods Four front panel buttons, cloning with Copy feature, PC with MeterView or LabVIEW software, and Modbus registers. Certified LabVIEW driver available.
Noise Filter Programmable 2 to 199 (0 will disable filter)
Display Update Rate Process/RTD: 3.7-5/sec; TC: 1.8-2.5/sec
Over Range Display flashes 9999
Under Range Display flashes -1999
Recalibration All inputs are calibrated at the factory; recalibration is recommended at least every 12 months.
Max/Min Display Stored until reset by user or meter is turned off.
Password Restricts modification of programmed settings
Non-Volatile Memory Settings stored for a minimum of 10 years.
Power Options 85-265 VAC, 50/60 Hz; 90-265 VDC, 20 W max or 12-36 VDC; 12-24 VAC, 6 W max.
Required Fuse UL Recognized, 5 A max, slow-blow; up to 6 meters may share one fuse.
Normal Mode Rejection 64 dB at 50/60 Hz
Isolation 4 kV input/output-to-power line; 500 V input-to-output or output-to-24 VDC supplies.
-6R5 & -6X5 models only: 100 V output-to-24 VDC supply
Warranty 3 years parts & labor
Warranty 3 years parts & labor