1
CW21 Certification Exam V2.0
Automatic Chronograph Module
September 21–25 | Harrison, Ohio |
Advanced Watchmaking Certification
Advanced Theory, Diagnosis &
Precision Servicing Edition.
Table of Contents
1. (Questions 1–25)
2. (Questions 26–
50)
3.
(Questions 51–75)
4.
(Questions 76–100)
5.
(Questions 101–120)
6.
(Questions 121–140)
7.
(Questions 141–150)
Section 1: Horological Theory & Chronograph Mechanics
,2
🟢 — In a chronograph movement, what is the fundamental difference
between "indirect drive" and "direct drive" chronograph seconds?
A) Indirect drive uses an intermediate wheel between the fourth wheel and chronograph
wheel; direct drive couples the chronograph seconds hand directly to an extended
fourth wheel pivot
B) Direct drive uses a friction clutch; indirect drive uses a tooth clutch
C) Indirect drive is always vertical clutch; direct drive is always horizontal clutch
D) Direct drive is only found in quartz chronographs
🔴🔴
In indirect drive, the chronograph seconds hand is driven through an
intermediate wheel from the fourth wheel, allowing the chronograph to be positioned
independently (e.g., central seconds). In direct drive, the chronograph seconds hand is
mounted on an extended pivot of the fourth wheel, meaning the chronograph seconds
hand is always coupled to the timekeeping train—requiring a different clutching
strategy (often a vertical clutch or a friction coupling).
🟢 — A watchmaker observes that a chronograph's central seconds hand
exhibits "flutter" (small back-and-forth oscillation) when the chronograph is stopped.
Which component is MOST likely responsible?
A) The blocking lever or brake is not fully engaging the chronograph wheel
B) The mainspring is too strong
C) The balance amplitude is too high
D) The automatic winding rotor is unbalanced
🔴🔴
,3
Flutter occurs when the chronograph train is not fully immobilized. The
blocking lever (brake) must securely engage the chronograph wheel to prevent any
movement. If the brake is misadjusted, worn, or contaminated, residual torque in the
chronograph train can cause the hand to oscillate slightly.
🟢 — What is the theoretical purpose of the "minute counter safety"
mechanism found in some high-grade chronographs?
A) To prevent the minute counter from advancing if the chronograph seconds hand is
not precisely at zero
B) To prevent over-winding of the mainspring
C) To lock the pusher during reset
D) To ensure the automatic winding does not interfere with the chronograph
🔴🔴
The minute counter safety (sometimes called a "minute counter lock" or
"zero safety") ensures that the minute counter only advances when the chronograph
seconds hand passes exactly through zero. This prevents false minute counting due to
hand misalignment or premature engagement.
🟢 — In a rattrapante (split-seconds) chronograph, what is the function of
the "isolating lever"?
A) To isolate the split-seconds wheel from the chronograph wheel when the split
function is activated, preventing drag
B) To isolate the chronograph from the timekeeping train
, 4
C) To isolate the pusher mechanism
D) To isolate the automatic winding system
🔴🔴
When the split-seconds hand is stopped, the isolating lever disengages the
split-seconds wheel from the chronograph wheel. This prevents the stopped split hand
from dragging on the still-running chronograph wheel, which would cause rate
deviations and wear.
🟢 — Which of the following correctly describes the "zero reset"
sequence in a column wheel chronograph with a vertical clutch?
A) Reset hammer strikes heart cams → clutch disengages → brake releases
B) Brake engages → clutch disengages → reset hammer strikes heart cams
C) Clutch disengages → brake engages → reset hammer strikes heart cams
D) Reset hammer strikes heart cams → brake engages → clutch disengages
🔴🔴
The correct sequence for reset is: first, the clutch disengages (removing
power from the chronograph train); second, the brake engages (immobilizing the train);
third, the reset hammer strikes the heart cams (returning hands to zero). This sequence
prevents damage to the heart cams and ensures precise reset.
🟢 — What is the "beat error" of a chronograph, and why is it particularly
important in chronograph timing?
CW21 Certification Exam V2.0
Automatic Chronograph Module
September 21–25 | Harrison, Ohio |
Advanced Watchmaking Certification
Advanced Theory, Diagnosis &
Precision Servicing Edition.
Table of Contents
1. (Questions 1–25)
2. (Questions 26–
50)
3.
(Questions 51–75)
4.
(Questions 76–100)
5.
(Questions 101–120)
6.
(Questions 121–140)
7.
(Questions 141–150)
Section 1: Horological Theory & Chronograph Mechanics
,2
🟢 — In a chronograph movement, what is the fundamental difference
between "indirect drive" and "direct drive" chronograph seconds?
A) Indirect drive uses an intermediate wheel between the fourth wheel and chronograph
wheel; direct drive couples the chronograph seconds hand directly to an extended
fourth wheel pivot
B) Direct drive uses a friction clutch; indirect drive uses a tooth clutch
C) Indirect drive is always vertical clutch; direct drive is always horizontal clutch
D) Direct drive is only found in quartz chronographs
🔴🔴
In indirect drive, the chronograph seconds hand is driven through an
intermediate wheel from the fourth wheel, allowing the chronograph to be positioned
independently (e.g., central seconds). In direct drive, the chronograph seconds hand is
mounted on an extended pivot of the fourth wheel, meaning the chronograph seconds
hand is always coupled to the timekeeping train—requiring a different clutching
strategy (often a vertical clutch or a friction coupling).
🟢 — A watchmaker observes that a chronograph's central seconds hand
exhibits "flutter" (small back-and-forth oscillation) when the chronograph is stopped.
Which component is MOST likely responsible?
A) The blocking lever or brake is not fully engaging the chronograph wheel
B) The mainspring is too strong
C) The balance amplitude is too high
D) The automatic winding rotor is unbalanced
🔴🔴
,3
Flutter occurs when the chronograph train is not fully immobilized. The
blocking lever (brake) must securely engage the chronograph wheel to prevent any
movement. If the brake is misadjusted, worn, or contaminated, residual torque in the
chronograph train can cause the hand to oscillate slightly.
🟢 — What is the theoretical purpose of the "minute counter safety"
mechanism found in some high-grade chronographs?
A) To prevent the minute counter from advancing if the chronograph seconds hand is
not precisely at zero
B) To prevent over-winding of the mainspring
C) To lock the pusher during reset
D) To ensure the automatic winding does not interfere with the chronograph
🔴🔴
The minute counter safety (sometimes called a "minute counter lock" or
"zero safety") ensures that the minute counter only advances when the chronograph
seconds hand passes exactly through zero. This prevents false minute counting due to
hand misalignment or premature engagement.
🟢 — In a rattrapante (split-seconds) chronograph, what is the function of
the "isolating lever"?
A) To isolate the split-seconds wheel from the chronograph wheel when the split
function is activated, preventing drag
B) To isolate the chronograph from the timekeeping train
, 4
C) To isolate the pusher mechanism
D) To isolate the automatic winding system
🔴🔴
When the split-seconds hand is stopped, the isolating lever disengages the
split-seconds wheel from the chronograph wheel. This prevents the stopped split hand
from dragging on the still-running chronograph wheel, which would cause rate
deviations and wear.
🟢 — Which of the following correctly describes the "zero reset"
sequence in a column wheel chronograph with a vertical clutch?
A) Reset hammer strikes heart cams → clutch disengages → brake releases
B) Brake engages → clutch disengages → reset hammer strikes heart cams
C) Clutch disengages → brake engages → reset hammer strikes heart cams
D) Reset hammer strikes heart cams → brake engages → clutch disengages
🔴🔴
The correct sequence for reset is: first, the clutch disengages (removing
power from the chronograph train); second, the brake engages (immobilizing the train);
third, the reset hammer strikes the heart cams (returning hands to zero). This sequence
prevents damage to the heart cams and ensures precise reset.
🟢 — What is the "beat error" of a chronograph, and why is it particularly
important in chronograph timing?
