7794
Industrial Amplifier for High Current / Low Impedance Operation
7794
Up to 200 Ap/100 Vp, DC to 150 kHz, Three-Phase
- Stable when driving a wide range of resistive, inductive or capacitive loads
- Field-selectable controlled-voltage or controlled-current operation
- Can be switched between rail supply modes to optimize for various load impedances
- Protection circuits guard against over/under voltage, over current, over temperature, and circulating ground currents
Key Performance Capabilities:
- 60A continuous at 13.8V DC
- 200A in-rush current capability
- 150 kHz small signal bandwidth
- ±95V DC capable
- >35 V/µs slew rate
- Four-quadrant operation (source and sink)
OVERVIEW
The 7794 is a powerful four-quadrant amplifier that offers up to 200 Ap power, DC – 100 kHz bandwidth, and controlled-current or controlled-voltage modes of operation. The 7794 works best into loads of 0.5 ohms or less. For greater voltage or current (up to 800 Ap) units can be combined in parallel or series.
Typically used when large currents are needed to drive very low impedances for long periods of time. Often used as a battery substitute for transient immunity testing requiring a battery as specified in EMC Test Standards for military, aviation and the automotive industries.
OUTPUT CHART
AC Output
Note: Testing performed at 208V/415V AC into resistive loads as specified. 7794 accuracy was measured when driven into a 10 ohm load with between 0.1V DC and 6V DC or between 0.2V AC and 5V AC presented at its inputs. Performance reported is typical into the specified load up to 20 kHz frequency levels. Above 20 kHz, slew rate may affect performance, reducing maximum voltage, current and power output. 7794 amplifiers can operate from 400V AC ±10%. Since these amplifiers have an unregulated power supply, low line conditions may slightly affect the maximum voltage potential.
| PEAK OUTPUT | RMS OUTPUT | ||||||||||
| 40mSec Pulse, 30% Duty Cycle | 5 Min, 100% Duty Cycle | 1 Hr, 100% Duty Cycle | 5 Min, 100% Duty Cycle | 1 Hr, 100% Duty Cycle | |||||||
| Ohms | Volts | Amps | Volts | Amps | Volts | Amps | Volts | Amps | Volts | Amps | Watts |
| 8 | 98 | 13 | 98 | 13 | 97 | 13 | 69 | 9 | 69 | 9 | 600 |
| 4 | 95 | 23 | 95 | 23 | 95 | 23 | 66 | 16 | 66 | 16 | 1000 |
| 2 | 88 | 44 | 88 | 44 | 88 | 44 | 60 | 30 | 60 | 30 | 1800 |
| 1 | 81 | 81 | 81 | 81 | 81 | 81 | 56 | 56 | 56 | 56 | 3200 |
| 0.5 | 72 | 144 | 72 | 144 | 72 | 144 | 50 | 100 | 50 | 100 | 5000 |
| 0.25 | 50 | 210 | 32 | 134 | 32 | 134 | 23 | 91 | 23 | 91 | 2000 |
| 0.125 | 23 | 197 | 23 | 194 | 23 | 191 | 16 | 133 | 16 | 130 | 2000 |
DC Output
Note: Testing performed in high-current mode.
| OUTPUT (Amperes) | ||
| Volts DC | 10 Min, 100% Duty Cycle | 1 Hr, 100% Duty Cycle |
| 13.5 | 80 | 60 |
| 24 | 115 | 106 |
| 32 | 120 | 115 |
| 48 | 60 | 40 |
| 80 | 50 | 50 |
PERFORMANCE
SPECIFICATIONS
Performance Specifications
Note: Testing performed at 208V/415V AC. 7794 amplifiers can operate from 400V AC ±10%. Since these amplifiers have an unregulated power supply, low-line conditions may slightly affect the maximum voltage potential. All testing was performed in Controlled-Voltage (CV) mode. Accuracy was measured when driven into a 10-ohm load with between 0.1V DC and 6V DC or between 0.2V AC and 5V AC presented at its inputs.
- Frequency Response (1 watt into 8 ohms)
- DC – 150 kHz: +0.1 to -5.2 dB
- DC – 30 kHz: +0.1 to -0.5 dB
- 8-Ohm Power Response (continuous duty):
- DC to 50 kHz: ±95 Vpk
- DC to 150 kHz: ±50 Vpk
- DC to 200 kHz: ±25 Vpk
- Maximum Continuous Output Power: 5000 watts RMS
- Slew Rate: >35 V/µs
- Residual Noise, 10 Hz to 20 kHz: Less than 250 µV
- Unit to Unit Phase Error: ±0.1 degrees at 60 Hz
- THD (DC – 20 kHz): Less than 0.25%
- Output Offset: Less than 200 µV
- Output Offset Current: Less than 10 mA DC
- DC Drift:
- From Cold to Maximum Operating Temperature: ±400 µV
- After 20 minutes of Operation: ±200 µV
- Output Impedance: 3.2 mΩ in Series with 2.2 µH
- Phase Response (10 Hz – 10 kHz): ±8.3 degrees
- Phase Error: ±0.1 degrees at 60 Hz
Input Characteristics
- Balanced with Ground: Three terminal barrier block connector, 20 kΩ differential
- Unbalanced: BNC connector, 10 kΩ single ended.
- Gain, Voltage Mode: 20 volts/volt; Current Mode: 20 amperes/volt
- Gain Linearity (over input signal, from 0.2V to 5V)
- DC: 0.0125%
- AC: 0.030%
- Max Input Voltage: ±10V, balanced or unbalanced
- Input Impedance: 20 kΩ differential
- Input Sensitivity: 3.0V input for 3800W output into 1 ohm (adjustable)
- Common Mode Rejection Range: -±11 VDC maximum
- Common Mode Rejection Ratio: 70 dB
Status Display, Control, I/O
- Front Panel LED Displays indicate: Ready, Standby, Fault
- Soft Touch Switches for: Run, Stop, Reset
- LCD Display: Can be configured for up to four simultaneous displays reporting one, two, or all four of the following: Vp, VRMS, Ap, ARMS Also reports any fault conditions that occur and suggests corrective action.
- Back Panel Power Connection: NEMA-style locking receptacle; matching AC connector also included
- Signal Output: 4-position terminal barrier block (OUTPUT / COMMON / SAMPLED COMMON / CHASSIS GROUND); resistor installed between SAMPLED COMMON AND CHASSIS GROUND is a 2.7-ohm, 2W, 5%, metal-oxide resistor
- Signal Input: User-selectable BNC or Barrier Strip, balanced or unbalanced
- Interlock Connector: 25-pin D-sub connector used for amplifier control and status applications; also used in multi-amplifier applications
Communication Capabilities
- Current Monitor: 20A/V ± 1%; 10A/V ± 1% (differential configuration)
- Reporting: System Fault, Over Temp, Over Voltage, Over Load
- Remote Control via Interlock Connector: Blanking control, Force to Standby, Reset after a fault
Protection
- Over/Under Voltage: ± 10% from specified supply voltage amplifier is forced to Standby
- Over Current: Breaker protection on both main power and low voltage supplies
- Over Temperature: Separate output transistor, heat sink, and transformer temperature monitoring and protection
Physical Characteristics
- Chassis: The Amplifier is designed for stand-alone or rack-mounted operation. The Chassis is aluminum with a black powder-coat finish. The unit occupies seven EIA 19-inch-wide units.
- Weight: 153 lbs (69 kg), Shipping 168 lbs (76.2 kg)
- AC Power: Three-phase, 208 VAC (±10%), 47-60 Hz, 30A AC service; (400 VAC (±10%), 15A model available)
- Operating Temperature: 10°C to 50°C (50°F to 122°F), maximum output power de-rated above 30°C (86°F).
- Humidity: 70% or less, non-condensing
- Cooling: Forced air cooling from front to back through removable filters via six 100ft3/min. fans. No space is required between rack-mounted amplifiers. Air filters are removeable from the rear via one fastener per side and may be eliminated if cabinet filtration is provided.
- Dimensions (HxWxD): 12.25” x 19” x 22.8” (31.3 cm x 48.3 cm x 57.9 cm)
PHOTOS
Controls, Indicators and Connectors
DIP Switch Settings
DOCUMENTS / DOWNLOADS
| 7794 Data Sheet | 7794 Manual | SIM Interlock Connector Pinouts and Functions | DXF Model for Chassis | Step File for Chassis |
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