Looking for docs => Rohde&Schwarz NGRE 40/30 Power Supply DC 0-40V 0-30A - Page 1
Forum section: electronics / repair

author: 9aplus
author_rank: Regular Contributor
timestamp: May 09, 2024, 01:08:37 pm
content: Looking for schematic or any kind of documentation for PSRohde&Schwarz NGRE 40/30 Power Supply DC 0-40V 0-30A 1200W

author: 9aplus
author_rank: Regular Contributor
timestamp: May 12, 2024, 03:12:00 pm
content: no one ?!

author: Kleinstein
author_rank: Super Contributor
timestamp: May 12, 2024, 03:21:35 pm
content: They typically don't publish schematics for the newer products (e.g. past about 1990). So probably no luck there. If you are lucky you may get some more module / software oriented (e.g. to do recalibration) service manual, but even this is not always available.

author: tonyalbus
author_rank: Super Contributor
timestamp: June 13, 2024, 10:00:55 am
content: Did you find it ? ,i am also looking for it, even a normal user manual i do not find.

author: 9aplus
author_rank: Regular Contributor
timestamp: June 16, 2024, 12:57:10 pm
content: No.No luck so far regarding schematic or manuals.On the other hand heave two units here, one sort of working, can at last compare the results.

author: tonyalbus
author_rank: Super Contributor
timestamp: July 14, 2024, 09:25:48 am
content: Hi,Found one on ebay, bought it, scanned it.the NL(Dutch) version is the Latest DA version, Digital readoutthe DL(German) is i think first version with Analog dialsfeel free to share or upload to the known manual websites.edit:The german version is to lanrge to upload. send me a DM with your emailadres, i WeTransfer it to you

author: 9aplus
author_rank: Regular Contributor
timestamp: July 21, 2024, 03:50:07 pm
content: @tonyalbusThank You!Very kind of youPM sent

author: pdenisowski
author_rank: Super Contributor
timestamp: July 22, 2024, 11:02:21 am
content: Quote from: 9aplus on June 16, 2024, 12:57:10 pmThe user manual is not available on our internal website either, but it looks like@tonyalbushas come to the rescue

author: 9aplus
author_rank: Regular Contributor
timestamp: September 14, 2024, 07:25:03 pm
content: Just like to report that have both (two) units now up and running.One as is, the second with calibration, cooling vent and two small bulbs replacement, only.Still testing but so far so good.Appreciate all assistanceThe only problem now, is how to make them bit more portable, heavy beasts must admit

author: 9aplus
author_rank: Regular Contributor
timestamp: September 18, 2024, 07:39:14 pm
content: Update...The signal lamps/bulbs on NGRE unit are on 48 V AC, replacement is difficult to find, last time saw that kindof indicators on old large scale crossbar telephone switching units, guess 45 years agoOn the second unit 2 of total 4 indicators are with broken glass.Perhaps "hard landing" during the times before the units reach me.It was possible to do "the surgery" on old indicators and now the 5K6 SMD R and white LED are doing the job.The 50 Hz can be noted, but guess half duty cycle is benefit hereThe cooling vents need some fresh oil in any case, now on both units all 3 vents are starting smooth and runabout the same time after the switch off. Recommended to all owners of similar units to open and check thecooling, you may hear the vents running, but that can be only one of three.Can put some internal pictures, in case someone is interested.

author: coromonadalix
author_rank: Super Contributor
timestamp: September 18, 2024, 09:35:34 pm
content: pls do ...

author: 9aplus
author_rank: Regular Contributor
timestamp: September 19, 2024, 02:40:26 pm
content: Here....

author: coromonadalix
author_rank: Super Contributor
timestamp: September 19, 2024, 02:48:59 pm
content: ooooooh k they put supplies in parallelsyou have 3 identicals sections, sums them up on page 17 ....it must weight around 80 pounds or more lollthks

author: 9aplus
author_rank: Regular Contributor
timestamp: September 19, 2024, 03:39:54 pm
content: More than 80 poundsBTW This must be one of rare unique combination of-el tubes (see that regulator on the last picture),semiconductors like power transistorsandchips with LCD for Volt and Amp meters

author: coromonadalix
author_rank: Super Contributor
timestamp: September 20, 2024, 05:03:23 pm
content: i would say to increase the led resistor a bit, the led seem very bright ... or 2 resistors instead of one, to halve the dissipated powerand since it's on 50 or 60hz the led will polarize itself .... since you run at half sine, 25 hz should not be perceived by the eye ?? or slightly ?not so portable loll

author: 9aplus
author_rank: Regular Contributor
timestamp: September 21, 2024, 05:19:13 pm
content: The brightness of LEDs is about the same, like the near bulbs.Around 8 mA AC going through. So far no burnout, let's seeConsidering to add some wheels on the short open plywood vertical box,sized to tight fit the PS box from behind.That also may make the cooling stream noise bit lower.

author: 9aplus
author_rank: Regular Contributor
timestamp: September 27, 2024, 01:52:27 pm
content: UPDATE IIIt seems that my units are custom made.Both going up to 50 V DC (under load) instead of 40 V DC as written on front.One unit is responding well on the load in regards of noise and cooling speed. The secondis going almost full speed from the turn ON.Must find that PTC/NTC whatever is somewhere in regulation chain.