I found out what the problem with my 136c temperature meter. It was the fuse. It was burn out. I removed the fuse and bypassed it by soldering a copper wire. Also the fuse for the 10A meter was burn out. I also bypassed it with copper wire.
What would be the effect if i don't use a fuse for the 10A meter? Will this make the ampere reading not accurate?
WTF!
Yesterday my Uni-T UT136B arrived and... it has no HOLD function, it has the display backlight instead.
Counterfeit?
Anyone has one of these?
It says UT136B on the upper right of the instrument. But...
Mmmmhhh... the pages for the specific variants of the UT136x are all down on UNI-T's website. The chinese one.
http://www.uni-trend.com.cn/productscatelist2_21_21_21_21.html
EDIT: The product pages are back, at least on the Chinese site.
Here's the 136B page: http://www.uni-trend.com.cn/productsdetail2.aspx?ProductsID=167&ProductsCateId=104&CateId=104
The picture clearly shows the HOLD button, and so does the manual.
Uni-T UT136B
Description:
Warning: New Update, the "HOLD " Button Changed to"Backlight"Button
The instrument of this series UT136B is a small hand-held 3 1/2 (3999 counts) digital multimeter featuring stable,highly reliable and anti-drop performance. It is provided with a LCD display (49mm x 18mm) for clear reading. The circuit design takes LSI double integral A/D converter as its core under the protection of an overload protection circuit, making it a superior modern instrument. Moreover, It can be used to measure or test DC and AC voltage, DC and AC current, resistance, capacity, diodes and in-circuit continuity (buzzer) test. It is kind of basic function/ low cost Multimeter not with high accuracy.
Features:
Auto Power Off ; Low Battery Display; Diode Test; Continue Buzzer
Input Imp. For DC Voltage Measure: >= 10Mohm
Data ; Max. Display: 3999
Tilt stand design, three observation angles is in favor of reading display
High sensitivity AC / DC voltage DC current measurement
Fit for schools, factories, families, and amateur wireless lovers
Small and compact design
It is made of superior material, durable and practical
Specification:
Power: 9V Battery
Product Color: Red and Iron Grey
The max display: 3999
Work Environment: 0?-40?
Storage Environment: -10?-50?
Function: DCV,ACV,DCA,ACA ,Diode
Product Dimensions: (13.5 x 6.5 x 3.5)cm / (5.31 x 2.56 x 1.38)"(L x W x H)
Product Net weight: 315g / 11.11oz
Function:
mA range: F1 fuse 5x20mm, F 0.5A H 250V
10A range: F2 fuse 5x20mm, F 10A H 250V
(When <= 5A continuous measurement is allowed, when > 5A continuous measurement less than 10 seconds at an interval more than 15 minutes)
DC voltage : 400mV/4V/40V/400V/500V ;±(0.8%+1)
AC voltage : 400mV/4V/40V/400V/500V ; ±(1.2%+3)
DC current : 400uA/4mA/40mA/400mA/4A/10A ; ±(1.0%+2)
AC Current : 400uA/4mA/40mA/400mA/4A/10A ; ±(1.2%+5)
Resistance : 400ohm/4000ohm/40kohm/400kohm/4Mohm/40Mohm ; ±(1.0%+2)
Capacitance : 4nF/40nF/400nF/4uF/40uF/100uF ; ±(4.0%+3)
Frequency : 10Hz/100Hz/1kHz/10kHz/100kHz/1MHz/10MHz ; ±(0.5%+3)
Duty cycle : 0.1% ~ 99.9%
Frequency: 40Hz ~ 400Hz. Display effective value of sine wave(average value) each measurement is applicable from 5% of range as reference.
Closer Look:
Warning: New Update, the "HOLD " Button Changed to"Backlight"Button
I got a UT136C for US$19.00 and Free shipping from Amazon. It is a Sinometer, but I hope it is a copycat of the Uni-T. I will send internal pictures after it arrives tomorrow.
It's now $15 with free shipping.
I just couldn't pass that up.
Oh, and all you need to do in order to get the probes to work well is to get some ultra-fine sandpaper (e.g., 1000 grit. I used 600 grit myself and it worked a treat) and go over the entire surface of the metal probe tips with it, including the point itself. This massively improves the contact reliability of the probes, and seems to bring them up to par with gold-plated tips for contact reliability (though the probe resistance is still higher than the best probes, almost certainly due to the choice of materials). Neither standard contact cleaner (haven't tried DeoxIT) nor IPA did anything to improve that.
Please, PLEASE, do not use sandpaper on probes. The probes usually are some kind of chrome or nickel plated onto cheaper metal like brass. Using sandpaper removes the plating and will make them prone to corrosion and constantly failing to make good contact. Usually what is preventing the probes from making good contact is residue from the molding process. The process can leave a very thin film of plastic/rubber/silicone or mold release on the surface of the probes. This needs to be removed without damaging the plating.
Instead, use fine steel wool and rub the probes with a bit of alcohol or some other solvent. This should remove the insulating coating without doing too much damage to the plating.