FDT5700 FREQUENCY INPUT
- Full Scale Frequencies from 10Hz to 100kHz
- Elevated Scale (Elevated-Zero) Ranges Available
- Adjustable Sensitivity Threshold
- Pull-up Resistor and Sensor Excitation Included
- 3-1/2 Digit User-Rangeable Display
- Urethane-Coated Circuit Boards
- AC or DC Power Options
The Model FDT5700 Frequency Input Transmitter provides an isolated DC output proportional to the input signal's frequency or pulse rate. Input / Output isolation is standard to guard against shock hazards in power measurements and against ground loop errors. Input ranges may be zero based or may be expanded (for example, 50-70Hz).
A rugged NEMA 4X splashproof, corrosion-resistant housing protects the transmitter in outdoor and industrial environments. The circuit boards are urethane coated for protection against condensation and contaminants. Model FDT5700 includes a 3-1/2 digit user-rangeable display to provide process indication in engineering units.
FDT5700 accepts input amplitudes from 25mV (50mV pk-pk, see specifications) to 350V peak without recalibration. A sensitivity adjustment provides optimum tradeoff between sensitivity and noise rejection for each application. Terminal connections allow the selection of two options: a pull-up resistor for dry-contact or open-collector inputs and a built-in DC excitation supply (approx. 18V) for lo-current DC proximity sensors (25mA max.)
Options include AC and DC power choices and reverse-acting transmitter (decreasing output with increasing input).
For field mount transmitters without a display, select any plug-in transmitter module plus our ENCL-1 NEMA-4X enclosure. (see Accessories page)
ORDERING INFORMATION
Model Numbers: FDT5700
Power: Add suffix A (Model FDT5700A) for AC power, D for DC power. Specify 115Vac, 230Vac, 12Vdc or 24Vdc.
Input Range: Specify any AC voltage or current range allowed by the "Input Capabilities" spec, below.
Input Sensitivity: The adjustment is normally factory-set for maximum sensitivity. If you wish a specific setting, please specify it on your order. See "Sensitivity Adjustment" below.
Output Range: Specify any DC voltage or current range allowed by the "Output Capabilities" spec, below.
Display Range: Specify display reading at low end and at full scale, including decimal point if required. See "Display Capabilities" specification, below. Note that reverse-acting display is possible - full scale reading downscale from low end. Display may be re-ranged by user.
Reverse-Acting Transmitter: Decreasing output with increasing input. Change model number to FDT5701(A or D).
Loop-Powered Output: 4/20mA "current sink" output stage for connection to devices whose inputs provide 24Vdc loop excitation. Change model number to FDT5702(A or D).
Conduit Connection: Standard: None. The enclosure has knockouts. Option NPT: Single 1/2 inch NPT fitting (glass-fiber reinforced nylon) at the bottom of the housing.
ELECTRICAL CONNECTIONS
Connections are made to 8 terminals within the enclosure:
1: Frequency Input (for normal inputs use terminals 1&2).
2: Input common.
3: +18Vdc (approx.) sensor excitation voltage output. See specifications.
4: Pull-up resistor (10K to +9V). Jumper terminals 1 and 4 together for use with dry contact or open-collector (NPN) inputs.
5: Output plus.
6: Output minus.
7: Power (AC or, if DC power option, DC plus).
8: Power (AC or, if DC power option, DC minus).SENSITIVITY ADJUSTMENT
The sensitivity trimpot sets the threshold below which the unit will not respond. Clockwise provides maximum sensitivity (see specs.) and Counterclockwise provides minimum sensitivity.
DETAILED SPECIFICATIONS
Frequency Input Capabilities: Minimum span 10Hz, max. frequency 100kHz. Low-end input may be zero, or may be as high as 2.5 times span (e.g. 20Hz span with 50Hz elevation, for 50/70Hz range). Input impedance 200K or greater.
Input Amplitude: 350V peak (700V pk-pk, 250V rms sine wave) maximum.
Threshold Adjustment: 25 turn trimpot. Max. sensitivity (full cw): 50mV pk-pk for frequencies below 1kHz. Increases to 1V pk-pk at 100kHz. Min. sensitivity (full ccw): 8V pk-pk for frequencies below 1kHz. Increases to 20V pk-pk at 100kHz.
Input Pull-up Resistor: 10K to +9V. Jumper terminals 1 and 4 to activate.
Input Sensor Excitation: Approximately 18Vdc unregulated, 25mA maximum current (terminal 3).
Voltage Output Capabilities: 1 volt minimum output span, -10 to +15V absolute limit. Offset ranges are allowed. Maximum output load, 10mA (1K at 10V output).
Current Output Capabilities: 1mA minimum output span, 0 to +25mA absolute limit. Positive offsets are allowed, negative outputs are not. Output drive capability, 24V (1200 ohms max. at 20mA output).
Display Capabilities: Low end and full scale readings may be anywhere between -1999 and +1999 counts. A fixed decimal point may be added in any position. Minimum span (full scale minus low end) is 10 counts. Reverse-acting display is possible (full scale reading downscale from low end). Display may be re-ranged by user.
Accuracy (factory calibration): +/-0.1% of span.
Linearity: +/-0.05% of span or better.
Isolation: 3-way (Power/Input/Output) 1,500Vac rms (2,100V peak).
Operating Temperature: -10 to +60˚C (14 to 140˚F).
Temperature Stability: +/-0.2% of full scale frequency per ˚C, or better.
Power Requirements: AC, 115 or 230Vrms, 50/60Hz, 2.5W. DC, 12 or 24V, 2.5W.
