INSTRUCTION MANUAL MODEL 1686A 3 to 14 VOLT DC POWER SUPPLY 1
TEST INSTRUMENT SAFETY WARNING Normal use of test equipment exposes you to a certain amount of danger from electrical shock because testing must sometimes be performed where exposed high voltage is present. An electrical shock causing 10 milliamps of current to pass through the hear t will stop most human heartbeats. Voltage as low as 35 volts dc or ac rms should be considered dangerous and hazardous since it can produce a lethal current under certain conditions.
Instruction Manual for MODEL 1686A 3 to 14 VOLT DC POWER SUPPLY 22820 Savi Ranch Parkway Yorba Linda, California 92887 3
TABLE OF CONTENTS page page TEST INSTRUMENT SAFETY................................ inside front cover MAINTENANCE............................................................................14 Fuse Replacement........................................................................14 Line Voltage Conversion.............................................................14 Adjustments.................................................................................14 Case Disassembly............................
INTRODUCTION The power supply utilizes thermostatically controlled fan cooling for improved heat dissipation and reliability while keeping bulk and weight to a minimum. The B+K Precision Model 1686 is a high quality 3 to 14 Volt DC Power Supply primarily designed for bench powering of automotive and marine electronic equipment. The Model 1686 has a maximum output current proportional to the voltage setting, the maximum current of 12 amps available from 13.8 to 14 volts and is reduced to 2.
SPECIFICATIONS OUTPUT VOLTAGE 3 to 14 VDC, ADJUSTABLE Ammeter Range 0 to 20A OUTPUT CURRENT PROPORTIONAL TO OUTPUT VOLTAGE; 3V 2.5A 5V 4.5A 9V 7.5A 12V 10.0A 13.8V 12.0A 14V 12.0A LOAD REGULATION (0 to Rated Current) ≤ 0.8% LINE REGULATION (108–132 VAC) ≤ 0.8% RIPPLE & NOISE ≤ 10 mV rms AC Input 115/230 VAC ±10%, 50/60Hz. POWER CONSUMPTION 400 W TEMPERATURE RANGE & HUMIDITY Operation 0° to +40°C ≤ 85% R.H. Storage –15° to +70°C ≤ 75% R.H. DIMENSIONS (H×W×D) 4.9 × 8.5 × 11.
CONTROLS AND INDICATORS 1. POWER Switch. Turns power supply on and off. Power on indicated by pilot lamp above switch. 7. OUTPUT “+” Terminal (Red). Positive polarity output terminal. 2. Power ON light. Lights when power is turned on. 8. OUTPUT “–” Terminal (Black). Negative polarity output terminal. 3. OVERLOAD Indicator. Lights when overload condition exists. 9. TIE POINTS (2A MAX). Red terminals are +, Black terminals are –. Load must not exceed 2 amperes. 4. VOLTAGE Control.
CONTROLS AND INDICATORS Figure 2. Rear Panel Figure 1. Front Panel Controls and Indicators, Model 1686A.
OPERATING INSTRUCTIONS SAFETY PRECAUTIONS EQUIPMENT PROTECTION PRECAUTIONS WARNING CAUTION The following precautions must be observed to help prevent electric shock. The following precautions will help avoid damage to the power supply. 1. Avoid using the power supply in ambient temperatures above +40°C (104°F). Always allow sufficient air space around the fan opening at the rear of the power supply and the top and side vent openings for effective air flow to prevent internal heat build-up.
OPERATING INSTRUCTIONS NOTE 3. The clip type TIE POINT terminals can be used to attach equipment requiring a maximum of 2 amps. Be sure to observe polarity when connecting equipment. 4. If more precision voltage readings are desired, connect a high-accuracy multimeter, such as the 0.5% B+K Precision Model 388A Digital Multimeter or equivalent across a pair of (+) and (–) TIE POINT terminals. Use solid copper hook-up wire with a minimum diameter of 12 AWG.
OPERATING INSTRUCTIONS CURRENT LIMITING The voltage is controlled by both VOLTAGE controls and is equal to the sum of the two V meter readings. Adjust voltage so that each power supply provides about half the total voltage. Overload (Foldback) current limiting gives protection against excessive overload and short circuit output. When an overload (foldback) condition exists, the unit drops out of voltage regulation and the OVERLOAD indicator will be illuminated.
OPERATING INSTRUCTIONS Figure 4. Connecting Two Power Supplies in Series for a 6-to-28 Volt Output.
OPERATING INSTRUCTIONS Figure 5. Connecting Two Power Supplies in Parallel for 3-to-14 Volt Output at Double Amperage.
MAINTENANCE WARNING 1. Make sure the power cord is unplugged. 2. Turn the unit over (bottom up) and reset the LINE VOLTAGE SELECT switch for the desired line voltage, 115V or 230V. The following instructions are for use by qualified personnel only. To avoid electrical shock, do not perform any servicing other than contained in the operating instructions unless you are qualified to do so. 3. A change in line voltage will also require a corresponding change of fuse value.
MAINTENANCE 2. Remove the ten screws that hold the case top to the chassis and front bezel. 3. Pull the front bezel away from the chassis to access the calibration adjustments. VOLTAGE AND V METER ADJUSTMENTS 1. Connect the multimeter (set to 20 DCV Range) to measure the dc voltage across the power supply (+) and (–) OUTPUT terminals. 2. Turn on the power supply, and set the front panel VOLTAGE control maximum (fully clockwise). 3. Adjust Trimmer VR3 for a reading of 14.50 ± 0.10 volts on the multimeter. 4.
MAINTENANCE 3. Adjust Trimmer VR5 so that the meter pointer on the A meter lines up with the 10 amp mark. 4. Remove the multimeter in series with the load, and reconnect it in parallel with the load to measure voltage (set to 20 DCV Range). 5. Adjust Trimmer VR2 fully counter clockwise, looking at the front of the unit. 6. Re-adjust the power supply front panel VOLTAGE control for a reading of 14.0 ± 0.5 volts on the multimeter if necessary. 7.
Service Information Warranty Service: Please return the product in the original packaging with proof of purchase to the address below. Clearly state in writing the performance problem and return any leads, probes, connectors and accessories that you are using with the device. Non-Warranty Service: Return the product in the original packaging to the address below. Clearly state in writing the performance problem and return any leads, probes, connectors and accessories that you are using with the device.
Limited One-Year Warranty B&K Precision Corp. warrants to the original purchaser that its products and the component parts thereof, will be free from defects in workmanship and materials for a period of one year from date of purchase. B&K Precision Corp. will, without charge, repair or replace, at its option, defective product or component parts. Returned product must be accompanied by proof of the purchase date in the form of a sales receipt.
TEST INSTRUMENT SAFETY (continued from inside front cover) 4. If possible, familiarize yourself with the equipment being tested and the location of its high voltage points. However, remember that high voltage may appear at unexpected points in defective equipment. 5. Use an insulated floor material or a large, insulated floor mat to stand on, and an insulated work surface on which to place equipment; and make certain such surfaces are not damp or wet. 6.
B&K Precision Corporation 22820 Savi Ranch Parkway Yorba Linda, California 92887 www.bkprecision.
