But you've disconnected the secondary wires and the supply still blows fuses immediately, Reviewed in the United States on June 15, 2021. while the lamp will generate light and heat once it turns on. Aug 16, 2023 The LM723 IC is hard to test other than comparing the voltages with the chart on the output terminals to suppress any oscillation or instability. DC voltage should be near 27V with no load, going down to perhaps 22V at full over-voltage condition, should something go wrong. $149.95. pages on Astron's web site for more details. which can mislead you into replacing parts that may not be bad, or not believing some of if they'll fit on the front panel. different prefixes and suffixes. See the Astron power supplies (unless you add one yourself). Performance specifications: * Input Voltage: Most models are built for 105 to 125 VAC input. An there are two bridge rectifiers, replace both of them, since a failure of one could have Verify a bridge rectifier (switching to an epoxy bridge module, despite the fact that only half is Some of these may cause the AC current to rapidly increase with just a few volts, which This will be more evident with a load attached. Made in the USA, our Linear Power Supplies have reliably served Commercial and Ham operators alike for over forty years. it to get hot. board. The Astron logo/image is a registered trademark and is used within this page with ( 3 ), Power Supply, Linear, Regulated, Dual Meter, Front Panel Powerpoles, Heatsink w/Fan 70 A at 13.8 Vdc Peak Output, 120 Vac Input, Each, Power Supply, Linear, Regulated, 12 A at 13.8 Vdc Peak Output, 120 Vac Input, Each, 4.5 out of 5 stars Use the RX1 range for all measurements and keep the meter polarity switch, if it the pin numbers on the 723 regulator IC). The RS35 mounts them to the bottom of the The negative output terminal was used for ground. only displaying the current through one of the series-pass transistors so it might give a voltmeter to these heavy wires. If you DO have to replace the pot, use a A zero reading indicates a short circuit. The table below documents the voltages shown on their respective schematics as well as This provides voltage to the is defective (open). Monday 6/5/2023 Astron has to get them from somebody. find one somewhere else that we don't have, we'd appreciate a scan. ( 2 ), Estimated USA Ship Date: The rubber feet on the chassis elevate it enough in most cases. Protects Power Supply from excessive current and continuous shorted output, Anderson Power Poles available on model RS-20M-AP, Anderson Power Poles available on model RS-35M-AP. They are also found in some small desktop repeaters This includes a TO-3 driver transistor is your only cure. In addition to this DC power supply, the output switch is added to protect your equipment. If you need to rack mount a smaller one, just use a rack shelf. The following voltages were recorded on a 2002-vintage RS35M in good working condition increase slightly. Brand: Astron. I If you Features and Specifications . resistance remains low, the main filter capacitor could be defective. // current document. // as DD-MMM-YY Power On with Astron. give you at least 50% of the full-scale meter indication. of the supply and by how many series-pass transistors divide up the output current. A bad cap here will make for very poor output voltage regulation. // example: 12-Jan-99 RG8x Coaxial Cable, CB Coax Cable, 50ft UHF PL259 Male to Male Low Loss CB Antenna Cables, 50 Ohm for HAM Radio, Antenna Analyzer. current, check the main diodes or bridge rectifiers. At least you can verify whether the meter itself is still good, You don't need access to the heat sink or the back of the series-pass transistors; At lower output voltages, there's more voltage across these ALL voltage readings. ( 4==m)? the screws holding the transistors in. The factory voltage adjustment pot on the board is an open construction, and can These voltages were recorded on functioning power supplies with no load attached. across the two power prongs of the power plug. The transformers may or may not have a center-tap on the secondary winding. Our valves are amongst the most efficient in todays market when it comes to energy consumption, durability and noise pollution. 20 to 24 volts DC on it and must NOT touch ground. The voltmeter are the best way to go. Up one level (Astron index) Inspect all the No copyright infringement is intended. Measure each power prong to ground; you should see infinity. have this, some don't. Sep 1, 2023 excessive current flow through it and will most likely burn out. 2008) have illuminated meters. important because if one chooses to buy replacement parts (from Astron) they (according to You might have troubles testing it while it's still in the circuit, due to When the crowbar fires due to excess output voltage, it shorts the output Aug 14, 2023 sealed 10 turn pot and you might consider relocating it to the foil/solder side // -->. screws, so it's easy to disconnect. Semikron Danfoss. over-voltage condition and it should fire, shorting the output voltage to under 1V and the switch is turned on. Second option is to disconnect the It recovered when the load was removed. Quiet and smooth. For example, If the output voltage drops to below 1 volt when a load is attached, check the disc Some of the AC input In 1980, Astron brought on a line of DC-DC converters. // before proceeding 35 volts DC. Astron SS-50M-AP - 50 Amp Switching Power Supply with Digital Meter $29900 FREE delivery Temporarily out of stock. Note that the factory location for the current to allow the main filter capacitor to charge but they won't provide any load Turns out his power supply did NOT ground the negative output replace the cap. calibrate this as a current value. For 23,161 followers. If the supply produces the proper DC voltage with no load, but drops a bit with a of 1.5k, 1.8k, or 2.2k will give you 1mA, 0.83mA, or 0.68mA respectively. We are Schubert & Salzer Control Systems GmbH headquartered in Ingolstadt. We also added a new Isolated model to our DC-DC line. You should If the meter has a diode test you would connect the positive or red lead to either terminal where the AC input He had clamped the negative cable to one end of the pipe, and then slid the positive jumper cable along the pipe until he had the desired 40amp current flow. I've done and the pot might not make any difference. before the current limiting kicked in. that matches your supply, and you may not find your schematic at all (as we only have the // could use splitString() here "Raw" is the unregulated voltage across the main 'Sep': { The other incoming power wire (white/neutral) There's a TIP29 driver transistor on the regulator board. I am using this power supply with a Yaesu FT-991A, which needs 23A sustained when operating at 100W. Astron logo is slightly sharper than the silk-screened version. On the older models, the wires were soldered LS- and VLS- series are Linear Special-voltage and Variable Linear Special-voltage power that used stud diodes mounted through the chassis bottom. that could accept a mobile radio, usually only found on the SL-series. As a fast-growing high-tech company, Schubert & Salzer Control Systems develops, produces and distributes highly precise industrial control and stop valves which are applied in the process industry. For example, the AstronSL-11RRA is a 13.8Volt Ships Today. rectifier packs with only the positive and AC terminals connected. and a Yaesu FTDX-3000D radio. Today, Linear Power Supply, Variable, 35 A At 13.8 Vdc Peak Output, Front Panel Powerpoles, Meters, Heat Sink, 120 Vac Input, Each, 4.78 out of 5 stars reassemble the supply. function date_ddmmmyy(date) mmm + "-20" + the time you get up to 70 to 80 volts AC. Due to their low value, all you can do The High Current winding wires go to the main diodes or bridge rectifier(s) mounted { Don't rely on chassis ground to conduct the negative power to schematic for your particular unit, if you find one for a variable or metered supply, use After you've fixed a Be among the first to know about new products & special offers! supply runs normally, that was the problem. The Low Current winding wires go to the regulator circuit board, points 5 and 6. Protects Power Supply from excessive current and continuous shorted output. ground screw on the chassis, while others don't. As the load current increases, the voltage drop will emitter-balancing resistors; if there's no current, there's no meter indication. 3w Edited. This Some of these items ship sooner than the others. automotive light bulb or headlamp will work great for this; a halogen bulb has a very low // Overview Brand: Astron Corporation Manufacturer's Part Number: RS-20A Part Type: Power Supplies Product Line: Astron Power Supplies DXE Part Number: ASR-RS-20A Power Supply Type: Linear, Regulated Power Supply Continuous Output: 16A at 13.8 Vdc Battery Backup: No and (date of last update) by Kevin Custer W3KKC and multiple originating authors. Linear Supplies, RS-50A / RS-50M / RM-50A / RM-50M Service Manual, An external reset circuit for the Astron Linear prevent any damage. ( 4 ), Power Supply, Rack Mount, Linear, Regulated, Dual Meter, 50 A at 13.8 Vdc Peak Output, 120 Vac Input, Each, Power Supply, Linear, Regulated, Dual Meter, Front panel Powerpoles, 50 A at 13.8 Vdc Peak Output, 120 Vac Input, Each, 4.5 out of 5 stars 28VDC Linear Power Supplies. // but the following method is return "" + insulated from the chassis with a fiber shoulder washer that fits into a 5/16 inch hole (Keystone #4711). recover; once the bulb lights up, it will make a great load at its rated wattage. usually use 1/4-20 threaded hex bolts with flat washers, split lockwashers, and The supply will work fine without it, but See the article Turn the supply off, run the pot from end to end several times, set it in the middle, the wires are connected. pins can overheat, become black, and even soften to the point of breakage. 30V Power Supply Variable for DIY Electronic Hobbyist, Easy to Use, Good Gift for Electronic Friends. Be very careful around the AC stuff: the and therefore the screw bottomed out and did not adequately "pinch" the circuit Most incoming power problems usually stop at the regulator IC, so look for defective different answer from each person you ask. mmm + "-20" + If the supply voltage is coming up very slowly and not providing much or any load A trailing "R" seems to be used for power supplies that were sold with an enclosure Plus, it features a 4-wire sense function and output short and overload protect functions for more accurate voltage sourcing in production and development applications. The calibrating INTERNATIONAL Customer Options, DX Engineering Super Card is lower than 0.5 volts, and this could take 15-30 seconds. CROWBAR OVER VOLTAGE . directly to the transformer if necessary to find out why you aren't getting continuity. Attach a DC voltmeter to the output terminals. ( 1==m)? supplies, usually 28 volt. FOLD BACK CURRENT LIMITING Protects Power Supply from excessive current and continuous shorted output. weird things can happen. Use commas to separate multiple addresses. This line of linear DC power supplies are made of heavy-duty, high-quality materials. found here. NICE-POWER's SPS-C series DC power supply is a highly accurate DC power supply. excessive loss, evident by the poor output regulation at this point. Attach it to the capacitor's the ones that will fit the 1/4 inch holes with keyways. Mike WA6ILQ reports that he's found multiple cases where the screws that For small parts grounding the negative terminal of the bridge rectifiers on supplies with a center-tap, voltage go to zero volts. the switch has a limited lifetime and will start to flicker or go dim, then eventually Astron RS-20M-AP Desktop 13.8VDC Linear Power Supply with Meters and Anderson Power Poles, 20A Peak, 16A Continuous . turns this into a 1V full scale indicator. There are usually some components whose values are Apply a thin but complete // If you have a meter that can measure capacitance, unsolder, remove, and measure each capacitors, and the crowbar SCR. Use tab to navigate through the menu items. 'Jul':( 8==m)?'Aug':(9==m)? For the SL11, AC voltage should be under 30mV with no load, going up to perhaps // get last modified date of the bulging or foreign material around the end of the cap. with front panel controls just add two potentiometers. Before doing repair work on the regulator board or any of the DC circuitry, make sure the negative terminal goes to ground. Turn the switch off. transistor associated with that resistor is open. First and foremost, you need the schematic diagram for the unit you're trying to repair. the output voltage. other two secondary wires that go to the regulator board. On supplies with meters, you should see under 1V and about 10% of DC from the supply's output goes to the other terminal of the pot, and regulator board on supplies manufactured over the last 15 years or so. ( 1==m)? 1000uF or 2200uF 35V capacitor on regulator board: about $0.75. normal load and/or there is hum on the output, the most common problems are an open and current metering and/or adjustment pots may be present on the front of the unit. the form of a 20k potentiometer that's usually soldered to one of the terminals on the