Physiologic Instruments VCC 600

Beschreibung

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	10, 20, 50, 100 kΩ *optional 1, 2, 5, 10 MΩ
±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	10, 20, 50, 100 Ω

*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.