B&K 1794 instruction manual

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your area. Before you purchase check the electrical parts list for the proper value rating, tolerance and description.

5.5.2ORDERING PROCEDURE : When ordering replacement parts from B+K Inc. please include the following minimum information :

1.Power Supply Type ( 1794 ).

2.Power Supply Serial Number ( For example, 03080001 ).

3.A description of the part ( if electrical include the circuit number ).

5.5.3CIRCUIT BOARDS : If a circuit board is damaged beyond repair, the entire assembly including all soldered-on components can be replaced. To remove or replace a board, proceed as follows :-

1.Disconnect all Sockets & leads connected to the board ( both soldered lead connections and solderless pin connections ).

2.Remove all mounting screws holding the board in the instrument.Remove any knobs, etc. that would prevent the board from being lifted out of the instrument.

3.Lift the circuit board out of the unit. Do not force or bend the board.

4.To replace the board, reverse the order of removal. Use care when replacing pin connectors. If forced into place incorrectly positioned, the pin connectors may be damaged.

5.5.4TRANSISTORS AND IC's : Transistors and IC's should not be replaced unless they are actually defective. If removed from their sockets during routing maintenance, return them to their original sockets. Unnecessary replacement or switching of semiconductor devices may affect the calibration of the instruments. When a transistor is replaced, check the operation of the part of the instrument that may be affected.

Replacement semiconductors should be of the original type ora direct replacement. When removing soldered-in transistors, use an approved anti-static suction-type desoldering tool to remove the solder from the holes in the circuit board.

An extracting tool should be used to remove the 14 pin integrated circuits to pre- vent damage to the pins. If an extracting the pins. Pull slowly and evenly on both ends of the IC. Avoid having one end of the IC disengage from the socket before the other end.

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Contents BK Precision Limited Two Year Warranty Table of Contents Limit Setting Output ON/OFF SwitchSection General Information Description Remote Programming With External 5K PotSection Specifications Section Installation Repackaging for Shipment Input TAP Selection for 230V OperationSection Operating Instructions Readjust the current limit in the remote sensing mode Reverse Current Loading Output CapacitanceReverse Voltage Loading Terms in this Manual Terms AS Marked on Equipment Operators Safety SummaryUSE the Proper Power Cord For Qualified Service Personnel only Servicing Safety SummaryDo not Service Alone USE Care When Servicing with Power onServicing shall be done only by Qualified personnel Section Service Instruction GeneralTrouble Shooting Techniques Repairs & Maintenance Page Parts Ordering & Replacing REF. PCB no PIN noPage Page Fuse Blows Fault Finding ProcedureFuse Blows Unregulated O/P Voltage Unregulated O/P VoltageNo O/P Voltage No Output VoltageNo DPM Indication No DPM IndicationDPM not Read Unit not Take Current Unit not Take CurrentUnit Directly Goes To CC Unit Directly Goes to CCPoor Line Regulation No Current ControlNo Current Control Poor Line RegulationPoor Load Regulation Poor Load RegulationCV, CC, LED not Glow External Programming Not OK External Programming not OKRemote Sense not OK L1791-FP-CNT-0603 PCB Assy Section Part List & Schematics1KPF/100V, Disc 2P2W SW Push ButtonPS-PREG-1791-0503 PCB Assly SW1 Grey Colour CAP for Push Switch SW2 SW3DPM/01 REV 01 X PS-PWR-L1791-0703A PCB Assly PS-AUX-DC-L1791-0503 PCB AsslyBack Trough Assly Front Panel AsslyMain Chassis Assly Front Panel Layout Back Panel Layout TOP View Bottom View of Model 1790 Front Panel Control PCB of 1790 Power Module PCB of 1790 PRE Regulator / AUX. P/S PCBs 1790 Precision Corp Service InformationPrecision Corp