We rarely look at analog multimeters, but have been politely requested to have a go at a Tekpower TP7040 review. This popular Mastech OEM budget device is a useful tool – as far as analog meters go – and is primarily used for measuring resistance, voltage and DC amperage. It has a decent build quality and large screen and a zero calibration adjustment on its resistance range.
Some Key Features
- AC/DC voltage ranges (to 1000V)
- Measures DC current (to 10A)
- Micro-amps/milliamps range
- Zero adjustment on low resistance
- Continuity with beeper
- Big screen with smooth needle
- Manual ranging
- Size: 7″ (178mm) x 4.2″ (107mm) x 1.8″ (46mm)
- Batteries (AA x2)
- Test leads (with protective caps)
- Operating instructions
In-depth Review of the TP7040
The TP7040 appeals mostly to old-school types looking for a basic, hands-on device that more readily shows fast-changing voltage sweeps and small resistance measurements. It is easy to operate and fairly accurate, albeit arbitrary at the same time depending on the user’s close reading skills.
You can measure up to 1000V (CAT-II 600V rated). This is not a True RMS responder, so you won’t get accurate AC readings on anything but a sine wave. This is fine until you try to measure the output signal of a variable frequency drive, for example.
DC current is up to 10A and it also has a µA/mA range, though there is no AC current range. The continuity checker is at the low resistance end and has a good response time, albeit with a scratchy beeper. A decibel range extends to 0-22db.
The resistance scale is perhaps the most useful facet, from x1 up to megohms. You can view tiny resistance measurements and the large screen makes it easier to spot smaller values. A zero calibration adjustment aids the accuracy at low resistance readings, though this has been reported to be inconsistent.
Input impedance: The meter’s low input impedance makes for clearer AC voltage measurements, where the high input impedance test circuits of DMMs makes them prone to picking up noisy signals and throwing off voltage measurements.
NOTE: As with many analog meters, there’s no off position on the TP7040, since it uses negligible power while sat idle.
Accuracy levels on voltage are around ±2%, though this also depends somewhat on the eyes of the viewer. As with most analog meters, resistance accuracy gets progressively more difficult to pin down at the higher end of the scale. Choosing the appropriate range is a must with these meters.
Build and Layout
Another area analog meters generally lose out on is hardiness, with the measuring mechanism being particular prone to failure when dropped. The TP7040 is quite tough, however, enclosed by a strong case and plastic boot. The finish is also good and the needle smooth running. The leads are fair quality and come with removable shrouds.
Display: The big screen sets it apart from most other analogs and is quite responsive. The glass is domed and sits proud, accentuating readings, though is more open to damage as a result. The dial might be confusing for some, with the AC voltage range color coded the same as DC amperage, for instance. It is also of course manual ranging, so beginners should take special note as it is easy to damage it through selecting wrong scales.
The safety rating is CAT-II 600V – surge protection 4kV. This category rating signifies it is built to test appliances and single phase circuits connected to a socket; not the socket outlet or installed wiring itself. You also wouldn’t want to be testing three phase systems with the Tekpower TP7040. Both the 10A and 500mA inputs are fused.
Tekpower TP7040 Pros and Cons
- Large ranges, good for those with eyesight issues
- Smooth, dampened needle action
- Easy to observe changing voltage
- Tough enclosure
- Continuity beeper could be better
- Domed screen prone to damage
- Zeroing issues at low temperatures
- No AC amperage range
- Cannot be hung
Analog meters are old hat nowadays, but are nevertheless sometimes preferred in certain settings where it is beneficial to see exactly what is going on as they can show a clearer, real-time feedback of a given signal. The Tekpower TP7040 review has a meter good for troubleshooting low energy equipment in a dry setting and where changing voltage and low resistance measurements are required.
It is especially good for DIY folks, and for the occasion of rapidly changing voltages, though it cannot replace the functionality and protection afforded by a comparable digital multimeter. It also can’t be hung up under a car or inside a control panel, but then again it is meant for general work on a bench or inside the home.
Alternatives: Tekpower make several other analog multimeters, including a pocket version and the TP8260L, which comes with a backlit screen. Simpson offers better quality again, or perhaps consider a DMM with an analog bar graph such as the UNI-T UT61E.