Series-PMT2

Supported Applications

The Dwyer Series PMT2 Particulate Transmitter is designed to measure particulate emission levels from dust collector discharge. Using DC coupled electrostatic induction sensing technology, the transmitter monitors a pA current generated as particulate passes near the probe and outputs a 4-20 mA signal that varies with the particulate level. The series supports air and compatible gases containing any type of conductive or non-conductive particulate.

Documented suggested ranges cover specific materials including:

• 5 to 100 pA range: Aluminum, paper, cotton, steel
• 5 to 500 pA range: Nylon, wood, fur, lead, silk, Mylar™, nickel/copper, silver/brass, gold/platinum, sulfur
• 5 to 1000 pA range: Acetate, glass, mica, human hair, acetate rayon, polyester, styrene (styrofoam), acrylic, Saran™, polyurethane, polyethylene
• 5 to 5000 pA range: Human hands, asbestos, rabbit fur, vinyl (PVC), silicon, PTFE, silicone rubber

Operating Conditions & Performance

The Series PMT2 operates within an ambient temperature of -40 to 145°F (-40 to 63°C) and a process temperature of -40 to 248°F (-40 to 120°C). The pressure limit is rated at 30 psi (2 bar), with a minimum air velocity requirement of 300 ft/min (1.52 m/s).

Performance specifications include:

• Detection Range: 5 to 5000 pA across six selectable range options
• Accuracy: ±5% of reading
• Averaging Time: 1 to 360 s (10 selectable options) used to dampen the signal if desired
• Particulate Size Detection: 0.3 microns and higher

The transmitter features a non-stick PTFE coated probe designed to prevent false readings from moist and conductive dusts, condensate, and dust buildup.

Configuration Options

The series is configurable across multiple dimensions including probe length, process connection type, enclosure rating for hazardous locations, and electrical entry options. The model number guide follows the format: PMT2 - [Probe Length] - [Process Connection] - [Enclosure Rating] - [Options].

Probe Lengths & Mounting Dimensions

Available probe lengths include 3", 5", 10", 15", 20", 30", and 36". Dimensional data varies by mount type:

• Threaded Mount (3/4" male NPT): Overall length 'A' ranges from 3 [76.20] mm to 36 [914.40] mm depending on probe selection.
• Tri-Clamp Option Mount: Includes a 1.5" tri-clamp kit with 1" male NPT; dimensions 'A' and 'B' vary by length (e.g., 3" probe: A=3-1/2 [88.90] mm, B=1-25/32 [45.24] mm).

Process Connections & Electrical Entries

The series supports the following process connections:

• -A: 3/4" male NPT (Note: BSPT process connections are not UL listed)
• -B: 1.5" tri-clamp kit with 1" male NPT
• -C: 3/4" male BSPT

Electrical connections consist of two 1/2" female NPT electrical entries as standard, or two M20 electrical entries available only with the A2 suffix.

Hazardous Location Approvals & Enclosures

The transmitter is offered in enclosures rated for hazardous locations:

• -U2 (UL IS): UL Type 4 (IP66); UL Listed Intrinsically Safe for Class I, Groups C and D; Class II, Groups E, F and G; Class III.
• -A2 (ATEX/IECEx IS): ATEX Compliant: CE 2813 @ II 1 G Ex ia IIB T4 Ga / II 1 D Ex ia IIIC T120°C Da. Enclosure rating is IP65 for ATEX/IECEx models.

Note: Units without the A2 suffix are not Directive 2014/34/EC (ATEX) compliant and are not intended for use in potentially hazardous atmospheres in the EU, though they may be CE marked for other Directives. Wetted materials include 316L SS, silicone, and PTFE.

Key Product Differences

The Series PMT2 distinguishes itself through selectable sensitivity ranges via a range and test selector switch. This switch allows the user to choose from six linear or logarithmic ranges (e.g., 5 to 100 pA, Log 5 to 500 pA) tailored to specific particulate types.

Key functional variations include:

• Test Mode: The switch can be set to output a fixed 4 mA or 20 mA signal to assist with setup and troubleshooting.
• Averaging Time: Configurable from 1 to 360 seconds in ten selectable options to dampen the signal response.
• Zero Calibration: Supports remote zero calibration. The PMT2 outputs approximately 3.5 mA while zeroing; normal operation resumes after approximately 3 minutes. Zeroing should not be performed while the dust collector is in operation.

The series includes optional accessories such as a stainless steel tag (-ST) and female M20 electrical entries (-M20). The transmitter is not field serviceable; units requiring repair must be returned to the manufacturer.