Series-APM-MPM-PPM

Supported Applications

The Dwyer Series APM, MPM, and PPM are 1/8 DIN digital panel meters designed for industrial process monitoring. The series encompasses three distinct measurement functions: the APM serves as a flow rate/totalizer; the MPM operates as a general-purpose configurable process meter with level monitoring capabilities including Round Horizontal Tank calculations; and the PPM functions as a pulse input flow rate/totalizer and tachometer.

These meters are engineered for applications requiring simultaneous display of rate and total, or dual-scale engineering units. The series supports control configurations such as duplex/triplex pump controllers via relay outputs and signal retransmission to PLCs or DCS systems through isolated 4-20 mA output options.

Operating Conditions & Performance

The meters feature a dual-line, 6-digit red LED display with digit heights of 0.6 in (15 mm) and 0.46 in (12 mm). Accuracy is specified as ±0.03% of calibrated span ±1 count.

• Operating Temperature: -40 to 149°F (-40 to 65°C)
• Storage Temperature: -40 to 185°F (-40 to 85°C)
• Enclosure Rating: NEMA 4X, IP65 front
• Power Supply Options: 85-265 VAC (50/60 Hz), 90-265 VDC, or 12-24 VDC ±10%
• Transmitter Power Supply: Built-in isolated 24 VDC output; capacity varies by model and power input type

The series accepts a wide range of inputs depending on the specific meter family: APM models accept 0-20 mA, 4-20 mA, 0-5 V, or ±10 V. PPM models support pulse or square wave (0-5 V to 0-24 V @ 30 kHz), TTL, open collector, NPN/PNP transistor, and switch contact inputs.

Configuration Options

The series offers extensive configuration options for outputs, communication, and expansion. Standard models are available with no internal output options or configured with relays and analog outputs at the factory.

• Relay Outputs: Options include 2 SPDT (Form C) or 4 SPDT (Form C) internal relays with interlocking capability, rated for 3 A @ 30 VDC and 125/250 VAC resistive load. External expansion modules can add up to four additional SPST (Form A) relays.
• Analog Output: Isolated 4-20 mA output option available for rate or total retransmission.
• Digital I/O Expansion: Modules provide 4 digital inputs and 4 digital outputs (with the capability to connect two).
• Communication: Modbus RTU serial communication is supported via RS-232, RS-485, or USB connections using optional adapters.

The meters include a Micro USB connection for programming and power. Programming utilizes the free Panel Meter Pro software resident on the meter, requiring no download to the PC. Time delays of 0 to 999.9 s are programmable independently for each relay.

Key Product Differences

The series is divided into three model families based on input type and application focus:

• APM Series (Analog Panel Meter): Designed specifically as a flow rate/totalizer accepting analog current or voltage inputs.
• MPM Series (Dual Line Configurable Panel Meter): A general-purpose process meter field-selectable for 4-20 mA, 0-10 VDC, and other signals. It includes unique level monitoring functions such as automatic Round Horizontal Tank calculation and 32-point linearization.
• PPM Series (Pulse Panel Meter): A multipurpose pulse input meter for flow rate/totalizing and tachometer applications, accepting various digital signal types including sine wave coils and switch contacts.

All three families share the same 1/8 DIN footprint, NEMA 4X/IP65 front panel rating, dual-line display architecture, and identical model numbering logic for power supply (e.g., -1xx for 85-265 VAC; -2xx for 12-24 VDC) and output configuration.