Field lessons for commissioning the SIPOS 5 FLASH electric actuator — eighteen practical notes.
1. Never loosen the potentiometer during commissioning. The potentiometer and the white gear to its left have a fixed factory-set relationship. For zeroing, simply turn the white gear on the left. Do not loosen the potentiometer and turn it to find the zero point. If the potentiometer has been loosened, refer to the "re-fitting the potentiometer" instructions when re-fitting it.
2. Calculating the signal gear unit ratio (rough estimation suffices): note the nameplate data of the quarter-turn gearbox. With gear ratio i and valve travel α degrees, the number of multi-turn output revolutions is:
Revolutions = i × α / 360 = i / 4 (for a 90° quarter-turn gearbox)
For a linear-stroke valve you need one parameter of the rotary-to-linear conversion element (drive screw, linear unit): how many millimetres the linear part travels per multi-turn revolution — call it L. For a drive screw, L is simply its pitch. With valve stroke H (mm) (typical screw pitches are 5, 6 or 7 mm):
Revolutions = valve stroke H (mm) / L
Select the nearest signal gear unit ratio above the calculated value.
3. Special case: when the calculated ratio falls very close to one of the gear steps — e.g. gearbox ratio i = 21:1 with 90° travel gives 5.25 revolutions, close to the 5.5 step. Considering that the actual valve opening may slightly exceed 90° (gearbox mechanical limit is typically 92°), that the actuator may overshoot slightly at the ends especially at higher speeds, and that the internal software reserves a small margin at the potentiometer zero, the ratio may need to go up one step before commissioning succeeds. Remedy: with the 5.5 step, slightly compress the 90° travel — e.g. after full closing is tight, wind back 3–5 turns by hand when setting full open, keeping the stroke within 90°. With the 14 step, do the opposite: extend the rotation angle as far as possible (never beyond the gearbox mechanical limit, and leave margin to avoid mechanical jamming).
4. The Economy version always sets the open end position first, then the close end position; the Professional version lets you choose either.
5. Economy version: DIP switch S1 sets the final output-shaft direction of rotation. When setting the full-open position first, make sure the valve movement matches the actuator buttons — pressing OPEN runs the valve towards open, CLOSE towards close. If not, S1 is wrong: switch S8 back to OFF, flip S1 to the opposite position, and restart commissioning from the beginning. If the wrong direction is only discovered after commissioning, flipping S1 is not enough — the end positions must be set again.
6. Professional version: the rotation direction is set by the close direction parameter. Once the end positions are commissioned, changing this parameter requires re-setting the end positions (an internal protection measure).
7. Economy version: DIP switches S2/S3 set the cut-off mode of the end positions. For quarter-turn valves always set them ON, i.e. travel-dependent cut-off.
8. Economy version: during end-position setting, watch that the indicator lamps match the manual. If not, something is wrong (operating error, torque fault, etc.) — start again or investigate the torque fault.
9. After the end positions are set, immediately run the actuator one full cycle locally (closed → open → closed). Any commissioning problem — torque fault, not closing tight, not opening fully — will show up at once.
10. Eight steps of end-position setting:
| Step | Professional | Economy |
|---|---|---|
| ① | Calculate the signal gear unit ratio | Calculate the signal gear unit ratio |
| ② | Centre the signal gear; valve at mid-position | Centre the signal gear; valve at mid-position |
| ③ | Run valve to full open (close) | Run valve to full open |
| ④ | Confirm full open (close) | Zero the potentiometer |
| ⑤ | Zero the potentiometer and confirm | Confirm full open |
| ⑥ | Run valve to full close (open) | Run valve to full close |
| ⑦ | Confirm full close (open) | Confirm full close |
| ⑧ | Check the commissioning | Check the commissioning |
11. Calculating the final output torque (quarter-turn application): for a 2SA5 plus quarter-turn gearbox, note two nameplates. The multi-turn unit (2SA5) nameplate gives a torque range, e.g. 10–30 Nm, at the multi-turn output shaft. The gearbox nameplate gives input torque T(in) and output torque T(out). The multiplication factor of the gearbox is K = T(out)/T(in). Economy version: with the closing torque range set 30%–100%, 100% corresponds to the nameplate maximum Tmax (30 Nm in the example), so T(2SA5) = Tmax × P%. Professional version: the set closing torque T(set) is already the multi-turn output torque. The final valve torque is the multi-turn torque times the gearbox factor:
Valve torque T = T(2SA5) × K = Tmax × P% × T(out)/T(in) (Economy)
Valve torque T = T(2SA5) × K = T(set) × T(out)/T(in) (Professional)
12. Calculating the final output thrust (linear-stroke application): find the torque-to-thrust conversion factor K of the conversion element (linear unit etc.), defined as K = output thrust F (kN) / input torque T (Nm). Then:
Thrust supplied to the valve (kN) = K (kN/Nm) × T(2SA5) (Nm)
13. The quarter-turn gearbox has mechanical stops — its output shaft can rotate at most 90°. Never stall the gearbox during commissioning, especially under electric operation. Learn the two limit positions first; near them, use jogging or the handwheel. If the situation is unknown, set a small closing torque first and increase it after successful commissioning.
14. Professional version: with a 4–20 mA analogue signal controlling the valve opening (position controller / analogue setpoint), note that the internal position controller has a dead band (0.2%–2.5%, self-adapting), so the default binary outputs 1 (tot. opened, NO) and 2 (tot. closed, NO) may never activate at the extreme positions. Adjust as follows:
| Parameter | Value | Meaning |
|---|---|---|
| travel pos. cl. | 2% | Close-end travel range |
| travel pos. op. | 98% | Open-end travel range |
| binary output 1 | TravLim2 op. NO | Open-travel limit (binary output 1) |
| binary output 2 | TravLim2 cl. NO | Close-travel limit (binary output 2) |
Users often confused travel pos. cl./op. with endpos.range cl./op., so the software renamed these contacts:
| Parameter | Value | Meaning |
|---|---|---|
| Inter.cont.CLOSE | 2% | Close intermediate contact range |
| Inter.cont.OPEN | 98% | Open intermediate contact range |
| binary output 1 | Inter.cont.OP | Open intermediate contact (binary output 1) |
| binary output 2 | Inter.cont.CL | Close intermediate contact (binary output 2) |
Note: the factory default of "close tightly" has been changed from no to yes, which makes the above unnecessary. However — particularly in torque cut-off mode — if the setpoint fluctuates around 2% (default close-end range 0%–2%), the motor will torque-trip frequently and overheat. We recommend setting close tightly back to no and using the table above instead.
15. When connecting the actuator analogue output (position feedback) to a DCS analogue input module, wire it as passive — the DCS must not power the loop (the actuator already powers the signal internally).
16. The analogue output is short-circuit protected: on an external short the protection cuts the output (neither voltage nor current measurable at the terminals). To reset, clear the short circuit, switch off, wait until all LEDs are out, then re-power.
The following two notes apply to actuators fitted with PROFIBUS DP.
17. If remote control was set to bus mode with the COM SIPOS software, the red LED flashing four times after local commissioning completes (S8 back to OFF) may indicate a bus communication fault. If the actuator operates locally, the commissioning itself is correct.
18. The Redundance DIP switch on the PROFIBUS termination board must always be set to the 2SPC position for SIPOS 5 FLASH (not emphasised on page 9 of the Chinese PROFIBUS manual).
