Seiko Tmi Caliber Nh34 Nh34a

Seiko Instruments (SII, TMI) Caliber NH34

Seiko Tmi Caliber Nh34 Nh34a

Manufacturer Seiko Instruments (SII), Time Module (TMI)
Caliber Number NH34, NH34A
Movement Type Automatic
Lignes
12”’
Diameter
27.4mm (29.36mm w/ spacer)
Height
5.32mm thick
Jewels 24
Vibrations Per Hour
21,600 bph
Lift Angle
53 degrees (needs confirmed)
Power Reserve
~41 hours
Hand Windable? Yes
Hand Winding Direction
Clockwise
Rotor Direction
Bi-directional (Magic Lever)
Anti-Shock System
Seiko Diashock
Regulator System
ETACHRON
Hand Count
4
Functions Central hours; central minutes; central sweeping seconds; central GMT hand; date at 3:00
Hacking Seconds?
Yes
Country of Manufacture Japan or Malaysia
Known Models
Venezianico Nereide GMT 39mm, Ikonik GMT Black Blade (Add yours in the comments below…)

The Seiko Instruments (SII) caliber NH34A is an automatic movement based on the Seiko branded 4R34. As part of the NH family of movements, the notable feature in the NH34 is the GMT complication (24 hour hand). This movement was released in Summer 2022.

Caliber NH34 VS NH35:

The main difference between the NH34 discussed here and the NH35 is that the NH35 is a 3-hander with a date, while the NH34 adds the additional 24 hour hand.

Differences Between NH34, NH34A and NH34B?

NH34 is the base caliber number and the letter designates evolution or updates to the movement. In other words, the “A” in NH34A indicates that it is the first generation of this caliber. If they change something in the movement later, it will be called a NH34B. At the time of this post, only the NH34A exists.

NH34 Accuracy Rating:

Time Module claims that the accuracy of calibre NH34 is adjusted at the factory to keep the time between +40 / -20 seconds per day. This rating is based on normal daily wear on the wrist in temperatures between 2 ºC and 23 ºC. When testing your watch for timekeeping, make sure it is fully wound.

In Seiko’s own words:

Due to the characteristics of mechanical watches, any actual daily rate may not fall within the range of time accuracy specified above dependent on the conditions of use, such as the length of time during which the watch is worn on the wrist, temperature, arm movement, and whether the mainspring is wound up fully or not, etc.” -Seiko User Manual

Power Reserve:

When your NH34 powered watch is fully wound, the power reserve is approximately 41 hours. When winding your watch, turn the crown clockwise slowly. You cannot overwind the movement.

NH34 Crown Position Functions:

0 (against the case): Clockwise = Manual Winding / Counterclockwise = Nothing
1 (pulled out one click): Clockwise = GMT hand / Counterclockwise = Date setting
2 (pulled out two clicks): Time setting clockwise and counterclockwise

Stem Removal:

To remove the stem, make sure the crown is in position 0 or normal position (not date or time setting position). There is a lever with a small indentation for your tool. Gently press down while pulling the stem out. See official instructions below for more guidance:

Seiko Caliber 4r36 Stem Removal

Replacement Cost:

Replacement prices for the caliber NH34A were found online in the range of $64.95 to $95 USD.

Recommended Service Intervals:

As per Seiko’s official recommended service intervals, they want 4R34 watches to be disassembled and cleaned by a Seiko service center once every 2 to 3 years “in order to maintain optimal performance of the watch for a long time”. Since the NH34A is based off of the 4R34, it is safe to assume the same recommendations apply. Ask the manufacturer of your watch for their recommendations.

In Seiko’s own words:

“The power transmission gear of the movement of this watch constantly receives force. To ensure that this mechanism works properly all the time, washing parts, changing oil, adjusting accuracy, checking functions and replacing consumable parts on a regular basis are important. The first overhaul after the purchase of your watch is particularly important for preserving long-time use of your watch. According to use conditions, the oil retaining condition of your watch mechanical parts may deteriorate, abrasion of the parts due to contamination of oil may advance or delay the time significantly, or the watch itself may stop.” -Seiko User Manual

Reference Number:

The official reference numbers (more complete caliber numbers) are as follows:

  • NH34A11J – Made in Japan, signed JAPAN on the rotor
  • NH34A11MN – Made in Malaysia*, signed MALAYSIA or no country of origin on the rotor

*It is widely assumed that modern NH movements without a country of origin are by default made in Malaysia, however, this is unconfirmed. We have contacted SII for more information about this, but they have not replied. The problem with assuming a non-Japan movement is made in Malaysia is that a movement without a country of origin can be made anywhere. With the vast number of NH movements being sold by China based trading companies (some even claiming the movements they sell are “genuine” and “made in China” within the same sentence), it is important for Seiko to address this so that the watch community can be certain where their movements are coming from. In fact, even in the official TMI tech documentation, they list two versions of the oscillating weight: Japan or Malaysia, with respective country of origin, but not mention of rotors with no country of origin. What’s going on, Seiko??

This clarification is also needed by microbrands and other non-Seiko brands using NH movements so that they are able to give accurate information to their customers about the origins of the components in the watches they produce. Sadly, some microbrand watch companies are nothing more than marketing companies that have watches designed and assembled by factories in China without actually knowing detailed technical information about the watches they advertise and sell. This is why you may come across brands that list their movements as being “made in Japan” with no country of origin on the rotor.

Seiko Only Version:

The Seiko only version of the NH34 is the Seiko caliber 6R54 (there is a section comparing these two movements on the 6R54 caliber listing).

Examples of Watches With This Movement:

Still waiting for other brands to make use of this movement. Add your watch to the comments below…
Additional Resources:
Caliber Corner is the world's most popular resource for watch movement pics, specs, mods and DIY repairs. Be sure to check out the member's forum and follow @calibercorner on Twitter, Instagram and YouTube (NOT Facebook). Join our mission to spread movement awareness! Login/Sign-up

Community Reviews & Questions:

  • Keep comments respectful and follow our community guidelines.
  • Keep comments on the topic of Seiko Instruments (SII, TMI) Caliber NH34

For off topic or general watch questions, post in the Caliber Corner Forum.

guest

34 Comments
oldest
newest most voted
Inline Feedbacks
View all comments
trackback
Seiko Caliber 4R34 Watch Movement | Caliber Corner
1 year ago

[…] is an unbranded version of the 4R34 movement known as the caliber NH34. It is based on the 4R34 and is still considered to be a Seiko movement, but the main difference is […]

Mark
Mark
1 year ago

Thank you. After troubles with the only Chinese made GMT that I have encountered, I wanted to see what other options are out there besides ETA or quartz. Glad to see Seiko with a new model. As usual, you guys have the most helpful link to a web search on the first page of returns. Keep up the great work.

Hans Groenewegen
Member
2 months ago
Reply to  Mark

@Mark: troubles with a GMT can happen with many a brand of watches, i.e. Junkers, Seiko Corp., Miyota Co., Rolex, Van der Gang etc. etc. They are respectively german, 2 x japanese, swiss and dutch. So one timepiece (GMT featured or not) doesn’t say anything of those brands themselves, whether they’re good or not, see ? It cán happen to ány brand sometimes. It’s just to be written-off at times.

Willem lassche
Willem lassche
1 year ago
  • Will a nh34a be a replacement for a DG3804?
trackback
Reseña RZE Ascentus GMT - SaFonaGastroCrono
1 year ago

[…] de lo que ha iniciado esta revolución del GMT es el asequible calibre NH34A de SEIKO, el que ha elegido RZE para impulsar el Ascentus. El NH34A es un calibre de 21.600 vph (3 […]

trackback
Miyota Caliber 9075 Watch Movement | Caliber Corner
1 year ago

[…] closest thing Seiko has to Miyota’s 9075 may be the caliber NH34A. It is also an affordable (more affordable actually) automatic GMT […]

Ian
Ian
1 year ago

Was a bit of a frenzy yesterday when Cousin’s put the price of its NH34’s to £10.10p The existing stock just evaporated with folks buying in bundles of ’em at that price.

Matt
Matt
1 year ago

thank you for this article! I have a Seiko GMT Modded watch with NH34 and the Seconds hand is stuck…will use this guide so I can self-repair it.

Ben
Ben
1 year ago

PHOIBOS Voyager GMT 200M Automatic Diver Watch uses this movement.

Bill Harbour
Bill Harbour
1 year ago

I’ve got a NH34A which will not quick adjust the 24hr hand and date. Came across this in my research as to how to fix the problem. Good info! Thanks,

Ronald
Ronald
1 year ago

I got an Aragon Millepede Evo Sun & Moon that uses the NH34. The interesting thing about this watch is that it repurposes the GMT functionality to turn an inner ‘floating’ dial instead of a GMT hand. This floating dial contains the graphics for the sun and moon, and is what gives this watch the Sun & Moon moniker

Lionel Gainsly
Lionel Gainsly
1 year ago

Thank you for this incredible website. I have just decided to add an NH34A to my collection. Now I just need to find the right one!

Michael
Michael
1 year ago

Borealis Sea Storm V2

Michael
Michael
1 year ago
Reply to  Michael

GMT

Manuel
Manuel
1 year ago

The OceanX Sharkmaster GMT range of watches use the NH34 caliber. Model no. are SMS-GMT-501 to 562. Another famous example for a microbrand using the NH34 are Venezianico with their Nereide GMT.

Dave M
Dave M
1 year ago

La Touraine Voyager GMT uses this movement

IMG_9617.jpeg
Larry Ruble
Larry Ruble
11 months ago

OceanevA uses this Movement

stevea
stevea
11 months ago

Tandorio GMT

Nathan
Nathan
1 month ago
Reply to  stevea

Are these original Seiko or Chinese clones?

Douglas Lancaster
Douglas Lancaster
9 months ago

Van Banner Adroit also uses this movement

Zbigniew Rzepczynski
Zbigniew Rzepczynski
7 months ago

Very informative. Thanks for your expertise.

Joe
Joe
5 months ago

Tsao Baltimore, a Maryland based watch company, has these inside their World Timer watches. This one features Baltimore on the bezel rather than New York, in Orioles orange no less. Plus this Ravens inspired design has their team colors:

Balt-Pilot Worldtimer DLC Raven – Tsao Baltimore

Joe
Joe
5 months ago

And a picture:

WTDLCRaven
Domingo P.
Domingo P.
4 months ago

Buenas.
Acabo de adquirir un reloj Pagani Design GMT automático con calibre NH34A y va de maravilla, precisión total, ni atrasa ni adelanta nada. Increíble.

BaoAnwen
Member
4 months ago

It seems that there is a design flaw in the calendar quick-set lever of the NH34. I bought 2 NH34 movements in China, and the quick-set function was normal for one of them before installation, but both were not normal after installation. I suspect that the quick-set lever may be loose. I wonder if any friends who have encountered the same problem can share their solutions

Zavie
Zavie
19 days ago
Reply to  BaoAnwen

Yes! Similar problem here. I’m pissed! Everything works fine, but as soon as I put the dial on, then hands, the GMT hand won’t set. On mine the date sets, but going in the other direction the GMT just clicks. The GMT hand works normally when I’m setting the time. I redid everything 3 times until I just give up and use it without setting the GMT hand.

Michael Moritz
Michael Moritz
3 months ago

For what it cost you to buy a TMI movement like the 34 or 35/36 you cannot find anything else with interchangeable parts that keeps your watches running well for a very long time
Love you Seiko

Charles
Charles
3 months ago

The Kienzle Gmt homage automatic watch has this movement.

mrdibujante
Member
2 months ago

Do you know if this automatic winds clockwise, counter or both?

keepthetime
Admin
2 months ago
Reply to  mrdibujante

Hi mrdibujante, from the specs chart above: “Rotor Direction: Bi-directional (Magic Lever)” indicates that it winds in both directions. Are you setting up your watch winder?

mrdibujante
Member
2 months ago

Yes

Nathan
Nathan
1 month ago
Reply to  mrdibujante

The automatic rotor winds in both directions, but if you are winding the crown manually, it’s only in the clockwise direction.

Bernd
Bernd
2 months ago

Panzera uses this movement for example in the FLIEGER 45G

Seagull Caliber St19

Join our mission to spread movement awareness!

Members Online

  • admin

Recent Forum Posts

Trending Comments

5

Miyota Caliber 2115

Found in the Aviator branded Special OPS AVW78341G350. It ticks along with +2 sec./month, thats…


4

ALTO Caliber A01

One of the coolest looking movements I've seen in a long time!


2

Miyota Caliber 2115

El casio marlin duro mvd 106 usa el miyota 2115. Cuando busco el repuesto aparecer…


2

ALTO Caliber A01

What's with these prices. It's 20k and has the same regulating system in my $500…


CJDUDHF
2

Sunon Caliber PE11

Sunon is a part of GUANGZHOU Pearl Time Group, PE11 is the only repairable movement…


Sponsors

34
0
Would love your thoughts, please comment.x
()
x