Physiologic Instruments VCC 600
The VCC 600 voltage-current clamp has been designed to be a flexible tool to aid the study of ion transport mechanisms by in vitro epithelial tissues. The VCC 600 provides the capability to control either the voltage or the current across the epithelium and is ideally suited for both electrophysiological studies as well as ion flux studies on epithelia.
Features
- PULSE GENERATOR- A built-in pulse generator which allows continuous monitoring of the tissue conductance
- DIGITAL 0.5" LED READOUT - of transepithelial voltage or current
- USER SELECTABLE CURRENT RANGES
- ELECTRODE OFFSET COMPENSATION
- FLUID RESISTANCE COMPENSATION - with user selectable ranges
- VOLTAGE OR CURRENT CLAMP - the ability to clamp either voltage or current across the epithelium
- DIGITAL 0.5" LED READOUT - of transepithelial voltage or current
- USER SELECTABLE CURRENT RANGES
- ELECTRODE OFFSET COMPENSATION
- FLUID RESISTANCE COMPENSATION - with user selectable ranges
- VOLTAGE OR CURRENT CLAMP - the ability to clamp either voltage or current across the epithelium
- BATH REFERENCE VOLTAGE - for use in microelectrode and pH stat experiments
- OPTIONAL HIGH VOLTAGE OUTPUT
- RECORDER OUTPUTS - for continuous monitoring of transepithelial voltage and current
- EXTERNAL INPUT - allows an arbitrary waveform to be clamped
- COMPUTER INTERFACE JACK, RACK MOUNTABLE
Specifications
GENERAL CHARACTERISTICS
- INPUT RESISTANCE >109 Ω differential
- COMMON MODE REJECTION >100 dB
- CLAMP OUTPUT ±13 V standard; ±35 V Option HV
- FREQUENCY RESPONSE 4 stage adjustment - internal pop switch
- DIGITAL DISPLAY 0.5" LED for easy readability
- TRANSEPITHELIAL VOLTAGE ±199.9 mV displayed, 10mV/mV recorder output
- GROUNDING Signal (circuit) ground is isolated from chassis and power grounds. Binding posts on the rear panel allow connection of circuit to chassis ground.
- FLEXIBILITY: Jumper selectable current measurement and fluid resistance compensation ranges
DISPLAYED CURRENT |
RECORDER OUTPUT |
FLUID RESISTANCE COMPENSATION |
±1.999 nA | 1 mV/nA | 10, 20, 50, 100 kΩ *optional 1, 2, 5, 10 MΩ |
±1.999 µA | 1 V/µA | |
±19.99 µA | 1 V/µ A | 1, 2, 5, 10 kΩ |
±199.9 µA | 10 mV/µA | 100, 200, 500 ,1000 Ω |
±1999 µA | 1 mV/µ A | 10, 20, 50, 100 Ω |
±1.999 mA | 1 V/mA |
*for use with isolated perfused rental tubules.
VOLTAGE-CURRENT CLAMP
OFFSET POTENTIAL COMPENSATION ±10 mV, ten-turn potentiometer and polarity switch.
FLUID RESISTANCE COMPENSATION push button adjustment with ten-turn potentiometer.For jumper selectable ranges at each current measurement setting. See TABLE.
DC CLAMP LEVEL
VOLTAGE-CLAMP: ±100 mV, ×1 or ×3 ten-turn potentiometer and polarity switch.
CURRENT CLAMP: range -150 % of maximum displayed current.
FUNCTION
ZERO: stand by mode, inputs V1 & V2 are internally grounded.
OPEN: open circuit, V1 & V2 are connected to sensing electrodes.
CLAMP: feedback loop is closed to control either current or voltage.
MODE
VOLTAGE/CURRENT CLAMP: selects either the transepithelial voltage or current to be clamped when FUNCTION is in the CLAMP position. (Note: Only CURRENT CLAMP mode is applicable to isolated, perfused rental tubules.)
LOCAL/REMOTE: selects control of the FUNCTION and VOLTAGE/CURRENT CLAMP switches to be from the front panel or from digital input to the REMOTE INTERFACE CONNECTOR. In REMOTE MODE the DC CLAMP LEVEL is disabled and an analog command signal is accepted from the computer.
PULSE GENERATOR
ON/OFF with ON indicator light
POLARITY selects +, - or bipolar pulses
SINGLE PULSE injects single pulse during normal period between pulses
RESET initializes interval timer
AMPLITUDE ×1, 0-10 mV in 1 mV steps. ×10, 0-10 mV in 10 mV steps
PULSE OUTPUT: ×10 above values
PERIOD 0.1-99.9 s Sets pulse interval. Thumbweel switch
DURATION 0.01.9.99 s Sets duration of each pulse. Thumbwheel switch
Note: The VCC 600 is available form us in bundle with an EasyMount Ussing Chamber System only. Please contact us for details.