7796
Industrial Amplifier for High Current / Low Impedance Operation
7796
Over 200 Ap / up to 180 Vp, DC to 100 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:
- 30A continuous at 28V DC
- 200A in-rush current capability
- 150 kHz small signal bandwidth
- ±180V DC capable
- >35 V/µs slew rate
- Four-quadrant operation (source and sink)
OVERVIEW
The 7796 power amplifier offers up to 200 Ap power, DC – 100 kHz bandwidth, and controlled-current or controlled-voltage modes of operation. The 7796 works best into loads of 2 ohms or less. For greater voltage or current (up to 800 Ap) units can be combined in parallel or series.
Typically used as a gradient amplifier in small bore, high gain MRI systems of up to 200 Ap per axis and to reproduce waveforms found in EMC standards like MIL STD 1275, MIL STD 461 and DO160.
OUTPUT CHART
AC Output
Note: Testing performed at 208V/415V AC into resistive loads as specified. 7796 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. Performance may be affected when operating into highly reactive loads or above 20 kHz, reducing maximum voltage, current and power output. 7796 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.
*Testing not performed.
| 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 |
| Open | 181 | 0 | 181 | 0 | 181 | 0 | 128 | 0 | 128 | 0 | 0 |
| 16 | 159 | 12 | 159 | 10 | 159 | 10 | 112 | 7 | 112 | 7 | 795 |
| 8 | 159 | 19 | 154 | 19 | 154 | 19 | 109 | 13 | 109 | 13 | 1463 |
| 4 | 158 | 39 | 152 | 38 | 152 | 38 | 107 | 27 | 107 | 27 | 2887 |
| 2 | 157 | 79 | * | * | 141 | 71 | * | * | 100 | 50 | 5004 |
| 1.5 | 148 | 99 | * | * | * | * | * | * | * | * | * |
| 1 | 140 | 140 | * | * | 71 | 71 | * | * | 50 | 50 | 2509 |
| 0.5 | 106 | 209 | * | * | 63 | 127 | * | * | 45 | 90 | 3999 |
| 0.25 | 53 | 209 | * | * | * | * | * | * | * | * | * |
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 | 34 | 25 |
| 24 | 42 | 30 |
| 48 | 95 | 80 |
PERFORMANCE
SPECIFICATIONS
Performance
Note: Testing performed at 208V/415V AC into resistive loads as specified. 7796 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. Performance may be affected when operating into highly reactive loads or above 20 kHz, 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.
- Frequency Response, DC – 30 kHz (1 watt into 8 ohms): +0.1 to -0.5 dB
- 8-Ohm Power Response (continuous duty):
- DC to 50 kHz: ± 150 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 255 µV
- THD (DC – 20 kHz): Less than 0.2%
- 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
- Unit to Unit 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 simultanteous displays report one, two, or all four of the following: Vp, VRMS, Ap, ARMS
- 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
| 7796 Data Sheet | 7796 Manual | SIM Interlock Connector Pinouts and Functions | DXF Model for Chassis | Step File for Chassis |
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