Duty Cycle Meter
Features
- Available in three digit heights: 0.56″ for panel mounting, 5.0″ (Mighty-5) for long-distance viewing.
- Measures ON or OFF period as a percentage of total period.
- Resolution of 1%, 0.1% or 0.01%.
- Inputs from NPN or PNP proximity switches, contact closures, digital logic, magnetic pickups down to 12 mV, or AC inputs up to 250 Vac.
- Trigger on positive or negative pulse edges.
- Frequency from .005 Hz to 10 kHz.
- 6-digit red or green LED display.
- Isolated 5, 10 or 24 Vdc excitation output to power sensors.
- Choice of isolated plug-in options for control and computer interface:
dual relays, 4-20 mA & 0-10 V analog output, RS232/485 serial I/O, low voltage AC & DC power. - 1/8 DIN case environmentally sealed to NEMA-4X from front panel.
- 1/8 DIN version certified to UL 3101-1, CAN/CSA-C22.2, EN 61010-1 (CE Mark).
Description
Duty Cycle Mode
Duty cycle is a measure of ON or OFF period as a percentage of total period. Duty cycle is determined by averaging an integral number of periods over a gate time which is selectable from 10 ms to 199.99 s. The same signal is applied to Channels A and B. The meter divides the average pulse width by the period between pulses and expresses this ratio in percent. A resolution of 1%, 0.1% or 0.01% is selectable. By selecting leading or falling pulse edges, the ON or OFF duty cycle can be displayed.
Duty cycle measurement is used to monitor modulated proportional control systems and pulse-modulated systems, such as radar, lasers or packet radio. For long periods, duty cycle can be measured by using the A and B channels of the Micro dual-channel counter to totalize AC line cycles and having the counter display the ratio of the two totals scaled to percent.
The Micro duty cycle meter uses the FR dual-channel signal conditioner board and Extended counter main board.
Universal Signal Conditioner
The dual-channel signal conditioner accepts inputs from proximity switches with PNP or NPN output, TTL or CMOS logic, magnetic pickups, contact closures, and AC signals from 12 mV to 250 Vac. Jumper selections provide optimum operation for different sensor types and noise conditions.
A built-in isolated 5, 10, or 24 Vdc excitation supply can power proximity switches and other sensors, and eliminate the need for an external power supply.
Built-in Flexibility
Plug-in isolated analog output, dual setpoint controller, and RS232/485 serial communications boards can upgrade Micro and Mighty Series duty cycle meters from a stand-alone monitor to system interface and control. The ability of the meter to output an isolated 0-10 V or 4-20 mA analog signal turns into an analog transmitter.
Micro Series meters can be powered from 95-240 Vac ±10% and 95-370 Vdc, or optionally from 12-34 Vac and 10-48 Vdc. Any setup functions and front panel keys may be locked out for simplified usage and security. The popular 1/8 DIN version with 0.56″ high digits is environmentally sealed to NEMA-4X (IP65) from the front when panel mounted, and is available with red or green LEDs.
Specifications
| Phase Angle Mode | |
| Item Displayed | Phase angle difference between two waves of same period |
| Display Units | 1°, 0.1°, 0.01° |
| Frequency Range | .005 Hz to 10 kHz |
| Accuracy | .01°, .005 Hz to 100 Hz, .1° at 1 kHz, 1° at 10 kHz |
| Maximum Timing Interval | 200 s |
| Duty Cycle Mode | |
| Item Displayed | ON or OFF duty cycle of periodic pulse waveshape |
| Display Units | 1%, 0.1%, 0.01% |
| Frequency Range | 0.005 Hz to 50 kHz |
| Accuracy | 0.01%, 0.005 Hz to 500 Hz, 0.1% at 5 kHz, 1% at 50 kHz |
| Maximum Timing Interval | 200 s |
| Display | |
| Readout | 6 digits, 7-segment |
| Digit Height | Available with 0.56", 1.0", 4.0" or 5.0" digits. |
| Color | High brightness red. Green available with 0.56" digits. |
| Range | -999999 to +999999 |
| Indicators | Four LED lamps |
| Inputs | |
| Types | AC, pulses from NPN, PNP transistors, contact closures, magnetic pickups |
| Signal ground | Common ground for channels A & B |
| Selectable Hysteresis | -12 mV to +12 mV, +30 mV to +60 mV, -30 mV to -20 mV, |
| -150 mV to +150 mV, +350 mV to +600 mV, -600 mV to -350 mV, | |
| -1.15 V to +1.15 V, +1.25 V to +2.1 V, -2.1 V to -1.25 V | |
| Selectable: 1 MHz, 30 kHz, 250 Hz | |
| Rolloff Filter | Selectable: 0, 3, 50 ms |
| Debounce Time |
| Timing Interval | |
| Periodic Timing Interval | Gate time + 30 ms + 0-2 signal periods |
| Gate Time | Selectable 10 ms to 199.99 s |
| Timeout | Selectable 10 ms to 199.99 s |
| Output & Display Update | Same as period timing interval |
| Power | |
| Voltage, std. | 95-240 Vac ±10% and 95-370 Vdc |
| Voltage, opt. | 12-34 Vac and 10-48 Vdc |
| Frequency | DC or 49-440 Hz |
| Power isolation | Safety-rated to 250 Vac, meter ground to earth ground, |
| DC to 60 Hz, 4.2 kVp per High Voltage Test |
| Excitation Output | |
| 5 Vdc | 5 Vdc ±5%, 100 mA max |
| 10 Vdc | 10 Vdc ±5%, 120 mA max |
| 24 Vdc | 24 Vdc ±5%, 50 mA max |
| Output isolation | 50 Vdc to meter ground |
| Environmental | |
| Operating Temperature | 0°C to 60°C |
| Storage Temp. | -40°C to 85°C |
| Relative Humidity | 95% at 40°C, non-condensing |
| Protection | NEMA-4X (IP-65) when panel mounted |
| Electrical Connections |
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Applications
Duty Cycle Mode
Duty cycle indicates the ON or OFF time in percent from 0% to 100% of period for repetitive pulse train. In the illustration, duty cycle is 100 x t / P. The same signal is applied to the A and B channels.
Duty Cycle and Elapsed Time of a Laser
Duty cycle can be used to indicate the ON time of a pulsed laser in relation to total time. Micro counters can also measure elapsed time, the number of pulses, average width in µs, the number of pulses, and total energy applied.
