Model 509 - Two-Wire, Square-Root Exctractor for Flow Monitoring

TWO-WIRE, SQUARE-ROOT EXTRACTOR FOR FLOW MONITORING
MODEL 509

Waterproof Housing

Connections Diagram

STANDARD FEATURES
Powered by 4-20 mA signal
2.5 V max voltage drop
160:1 signal range
0.35 in (8.9 mm) liquid crystal display
100 to 2,000 count display span
Selectable dummy right-hand zero
40 to +85°C operation
Compact, 74 mm (2.9 in) diameter sealed die-cast metal housing
Shock resistant to 55 g

OPTIONS
1/2 EMT conduit fitting
1/2 NPT pipe fitting
Relay track mounting adapters
External explosion-proof housing

Model 509 is a two-wire current-loop indicator with square root response for use with differential-pressure flowmeters and any other transducers with a squared output. It is powered directly by the 4-20 mA loop, with a maximum voltage drop of 2.5 V. No separate power connections are required. This reduces field wiring costs and provides immunity from most electrical noise encountered in process environments. The 509 is similar in appearance and mounting to the 508A, which has a linear response.

READOUT IN ENGINEERING UNITS
The 509 is designed so that 4 mA corresponds to zero flow and 20 mA to maximum flow. It provides extensive span adjustment so that it can read out directly in percent or in engineering units, such as GPM or liters/sec. Its liquid crystal display provides 3 1/2 active digits (1,999 counts), a jumper-selectable dummy right-hand zero and three selectable decimal points. A fine zero adjustment is available to tune out any small offset in the nominal 4 mA signal from the flow transducer. Zero and span are each adjusted with a precision multiturn potentiometer, which is accessible through a hole in the front panel.

EXCEPTIONAL RANGE AND ACCURACY
The 509 uses a proprietary analog circuit, which gives it exceptionally high accuracy and wide dynamic range. The error is within the display resolution of ±1 count for nominal signals from 4.1 mA to 20 mA. This corresponds to a dynamic range of 160:1 for the signal and 13:1 for the reading after square root extraction.

DESIGNED FOR HARSH ENVIRONMENTS
The 509 is rated for operation from 40 to +85°C (40 to +185°F) with specified accuracy. The case is made of die-cast metal and is waterproof to 35 kPa (5 psi). The electronics are firmly connected to the case top, so that the meter can withstand high vibration and shock. Mounting options include a male 1/2 EMT conduit fitting or a male 1/2 NPT pipe fitting in lieu of the normal rail or surface mount. These fittings eliminate the external screw terminals and provide a NEMA-4X rating.

EXPLOSION-PROOF HOUSING OPTION
An external NEMA-7 explosion-proof and NEMA-4 waterproof enclosure is available as an option for use in hazardous locations in Class I, Groups B, C, D; and Class II, Groups E, F, G. It offers a glass viewing window, two female 1/2 NPT pipe fittings, all required internal mounting hardware and mounting flanges for a wall or bulkhead. FM and CENELEC certification are standard for the housing.

The electronics of the 509 have been designed for intrinsic safety. FM, CSA and CENELEC intrinsic safety certifications are pending.

A Model 509 may be added to an existing 4-20 mA loop. No additional wiring is required, since the meter is powered directly by the current loop.

SPECIFICATIONS

INPUT
Signal: 1-5 mA, 4-20 mA or 10-50 mA (jumper-selectable)
Display response: k (square root of input signal)
Display span for 16 mA signal span: 0 to 2000 counts
Zero calibration range: 3.9 to 4.2 mA
Forward voltage drop, max: 2.5 V up to 50 mA
Input resistance: 12.5
Protection: 200 mA forward, 1000 mA reverse
NMR: 46 dB, 50/60 Hz and 12 mA
CMR, meter to case: 120 dB at DC-60 Hz and 12 mA
CMV, meter to case: 700 Vp
RFI susceptibility: Less than ±0.5% of span with conduit fitting or external explosion-proof housing in 10V/m field strength at 27 or 440 MHz

ACCURACY AT 25°C
Maximum signal for 1 count error: 4.1 mA
Minimum display for rated accuracy: 8% of full scale
Maximum error: ±0.1% of span ±1 count
Zero tempco: ±0.1 count/°C typ, ±0.2 count/°C max
Span tempco: ±0.005% of span/°C typ, ±0.015% of span/°C max

SQUARE ROOT EXTRACTION
Square root technique: Linear V-to-F with pulse-width modulator
A-to-D conversion technique: Dual-slope, average-value
Integration period: 100 ms
Read rate: 2.5/s

DISPLAY
Type: 7-segment, LED
Height: 0.35 in (8.9 mm)
Symbols: 1.8.8.80 (3 1/2 active digits plus jumper- selectable dummy right-hand zero)
Decimal points: Three positions, jumper-selectable
Underrange: Minus sign displayed

ENVIRONMENTAL
Operating temperature: 40 to +85°C (40 to +185°F)
Vibration: 0.06 in (1.52 mm) double-amplitude cycled at 10-80 Hz
Shock: 55 g half-sine, 9-13 ms duration
Waterproof pressure: 35 kPa max (5 psi)

MECHANICAL
Weight: 14 oz (400 g)
Diameter: 2.9 in (74 mm)
Height, including barrier: 1.9 in (48 mm)
Electrical connections:
509-1: 3-terminal barrier strip with #6 screws
509-2 & 509-3: Two 0.3 meter long #18 stranded wires

MOUNTING METHODS
509-1

Surface mount with four #6 rear-entry screws from backside of bulkhead.

Snap mount into 2.50 in (63.5 mm) relay track.

Surface mount with two #8 front-entry screws. Requires MAT1 adapter plate.

Snap mount into 2.75 in (69.9 mm) or 3.00 in (76.2 mm) relay track. Requires MAT1 adapter plate.

Snap mount into DIN relay track per CENELEC standard EN 50 022. Requires MDT1 rail clamp.

Push mount into explosion-proof housing EPW3.
509-2

1/2-inch EMT male conduit fitting
509-3

1/2-inch NPT male pipe fitting