ef

1. ESP Start-up and
operation

2. Preliminary operations for start-up
Start-up team includes the following:
- production operator;
- 2 electricians from Novomet-Service LLC;
- maintenance & operation electrician;
- drilling team manager.
ESP Start-up

3. Before start-up proceed as follows:
- make visual inspection of ESP surface equipment, check
switchboard (VSD) and step-up transformer grounding;
- make sure downhole cable armor is grounded to the
christmas tree;
- check the switchboard, step-up transformer, junction box;
check tightness of the bolts on electrical components;
check connection to the zero point between step-up
transformer and switchboard (VSD);
- check phasing in the junction box with a high-voltage
phase indicator.

4. Attention! Idle start-up is prohibited for VSD for PMM
when the step-up transformer is connected. In this case
during the startup the VSD determines the position of the
rotor, and the frequency at the output terminals will be 6
Hertz, while the peak value will gradually rise to the
nominal value of the power grid, i.e. to 380 V. It will lead to
oversaturation of the magnetic system of step-up
transformer and to high current value close to the short-
circuit current.
Attention! When using VSD for PMM, it is prohibited to
check the phasing with a high-voltage phase indicator.
Phasing should be checked with an ohmmeter.
Attention! When running VSD for PMM do not use output
filter between the VSD and transformer, because it will
cause pulse distortion of the VSD output voltage, and it will
be impossible to determine the rotor position.

5. Person in charge of start-up and commissioning should
know the following:
- capacity, head, operating range and completion of the unit;
- production casing ID, tubing OD to determine annulus volume;
- setting depth;
- horsepower and type of the motor (kW) and required inflow;
- rated current of the motor, idle current;
- rated voltage of the motor; required voltage at the tap of the
step-up transformer;
- rated frequency of the electric motor;
- type and density of kill fluid.
If all the issues with the workover team are cleared, accept the
completed operations note of ESP from the workover team.

6. ESP Start-up
Before start-up:
- calculate the required voltage at the transformer output
using the formulas below and set the closest higher tapping
compared to the calculated:
a) for switchboards with direct and soft start:
b) for VSDs for acynchronous motors:
c) for VSD for PMM:
PMM (permanent magnet electric motors) with rated shaft
rotational velocity of 3000 rpm may be operated at up to
4200 rpm
U
F
U
U M
dem 

 )
50
/
*
(
2
)
/
380
(
*
)
( 1
2 U
U
U
U dem 


U
F
F
U
U rated
M
DEM 

 )
/
*
(
2

7. Voltage losses per 1000 meters of cable line:
m
L
value
table
U
cab
gen
1000
.




8. Voltage losses in copper conduct
cable, section 3х16 mm, V (per
1000 meters)
Voltage losses in copper conduct
cable, section 3х21 mm, V (per
1000 meters)
Voltage losses in copper conduct
cable, section 3х25 mm, V (per
1000 meters)
Voltage losses in copper conduct
cable, section 3х33 mm, V (per
1000 meters)
Jnom
el.
mot.,
А
Formation
temperature, 0
С
Jnom
el.
mot.,
А
Formation
temperature, 0
С
Jnom
el.
mot.,
А
Formation
temperature, 0
С
Jnom
el.
mot.,
А
Formation
temperature, 0
С
40-60 70-90 > 100 40-60 70-90 > 100 40-60 70-90 > 100 40-60 70-90 > 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
14,6 28 32 35 14,6 21 24 27 14,6 18 20 23 14,6 13 16 17
18 34 39 44 18 26 30 33 18 22 25 28 18 17 19 21
21 40 46 51 21 31 35 39 21 26 29 33 21 19 22 25
22 42 48 53 22 32 37 41 22 27 31 34 22 20 23 26
24 46 53 58 24 35 40 45 24 29 34 37 24 22 26 28
25 48 55 61 25 37 42 46 25 31 35 39 25 23 27 29
26 50 57 63 26 38 43 48 26 32 36 40 26 24 28 31
27 51 59 66 27 39 45 50 27 33 38 42 27 25 29 32
28 53 61 68 28 41 47 52 28 34 39 44 28 26 30 33
29 55 64 70 29 42 48 54 29 35 41 45 29 27 31 34
30 57 66 73 30 44 50 56 30 37 42 47 30 28 32 35
32 61 70 78 32 47 53 59 32 39 45 50 32 29 34 38
33 63 72 80 33 48 55 61 33 40 46 51 33 30 35 39
34 65 74 83 34 50 57 63 34 42 47 53 34 31 36 40
35 67 77 85 35 51 58 65 35 43 49 54 35 32 37 41
36 69 79 87 36 53 60 67 36 44 50 56 36 33 38 42
37 70 81 90 37 54 62 69 37 45 52 58 37 34 39 43
38 72 83 92 38 55 63 71 38 46 53 59 38 35 40 45
… … … … … … … … … … … … … … … …
40 76 88 97 40 58 67 74 40 49 56 62 40 37 43 47

9. Switchboard/VSD
settings and
protection

10. How to set overload protection
(OP)
 Overload protection is intended to shutdown electric motor when
the operating current exceeds rated current; the aim is to prevent
overheating and short circuit of the stator winding. Adjustment of
the overload protection should be performed before ESP startup.
The adjustment procedure should comply with the Operation
Manual of the switchboard/VSD .
 Setting value of overload protection for microprocessor controller
switchboards and insulation control protection is calculated by the
formula:
 OP = 1.05 * Irated,
 where: OP is the setting value of overload protection;
Irated is the motor rated current in amper (А).
 Overload protection setting actuation time is 30 sec.

11. How to select step-up
transformer voltage (U tap)
 Optimum voltage at the step-up transformer output
should be selected after pumping-out of the kill fluid and
putting ESP into stable operation. Voltage optimization
should be applied after changing ESP operating mode.
The selection should be done through step-by-step
voltage reduction, i.е. switch-over of the transformer taps
after approval of the required shutdowns. When reducing
the voltage, keep monitoring motor operating current. If
the current goes up, bring the tapping switch of step-up
transformer to the previous position.

12. How to set motor underload
protection
 - Underload setting during start-up should be
15% less than motor operating current.
 - Underload setting during commissioning of the
well should be set according to Table B.1 after
the optimal voltage is selected.

13. Load, %
% of reduced
value Iwork
Setting value for Trip on underload for
switchboard 
70 and
more
15 (load) -15%
from 50 to
70
10 (load) -10%
Less than
50
5 (load) – 5%

14. Protection against voltage spikes
 Voltage spikes protection is necessary for stable
ESP operation.
 High-voltage protection setting: Umax = 420 V
(110%). Actuation time delay should be set to 5
seconds.
 Low-voltage protection setting: Umin = 340 V
(90%). Actuation time delay should be set to 5
seconds.

15. Protection against current phase
misbalance
 Protection against current phase
misbalance is necessary to ensure stable
operation of electric motor and maximum
run-life. Recommended misbalance of
current phases should not exceed 15%.
 Percentage of current phase misbalance
should be calculated by the following
formula:
100
max




Iav
I
I

16. Protection against voltage phase
misbalance
 Protection against voltage phase
misbalance is necessary to ensure stable
operation of electric motor. Misbalance of
voltage phases should not exceed 5%.

17. Insulation resistance protection of
the ‘step-up transformer – cable –
electric motor’ assembly
 Insulation resistance protection of the ‘step-up transformer – cable –
electric motor’ assembly is intended to prevent short circuit of
electrical components. Protection setting should not be less than 30
kohm.
 During conversion from standard mode to operation without control
of insulation resistance):
 Switch off insulation control device or function;
 Actuation time of overload protection should be reduced to 5 sec.;
 Automatic restart should be switched to ‘Lock’ position for overload
protection;
 When necessary, disconnect zero point.

18. Backspin protection
 Backspin protection is intended to prevent ESP starting
during fluid discharge from the tubing. The setting should
be 5 Hertz. If switchboard includes this protection,
automatic restart period for this switchboard should be
set from 1 to 5 minutes.

19. Checking correct rotation of ESP shaft
and tubing leak.
 Once the ESP system is started, it is necessary to check
rotation through the following methods:
 а) using current and load of electric motor: check load
and current of the electric motor with direct and reverse
rotation direction (the correct rotation direction will
demonstrate higher current and load of electric motor);
 b) pressure test of the christmas tree: while the unit is in
operation, gradually close the manifold valve, keep
checking the pressure increase rate and pressure value
at the wellhead pressure gauge, make this operation for
direct and reverse rotation (with the correct rotation
direction the pressure increase rate and pressure value
will be higher).

20. Start-up and commissioning procedure
 During start-up, commissioning and operation it is prohibited to
operate ESP without fluid inflow from the well. lack of fluid flow
along the motor will lead to overheating.
Submersible electric motor series Continuous operation duration
ESP system with a submersible
motor up to 32 kW inclusive
not more than 2 hours
ESP system with a submersible
motor from 32 kW to 45 kW
inclusive
not more than 1 hour
ESP system with a submersible
motor exceeding
45 kW
not more than 30 minutes

21. Inflow calculation based on production
rate
(m3/day)
(m3)
)
/
60
(
*
24
*
*
)
1
2
( Т
V
Нд
Нд
Q
Q flowmeter
INFL 


annulus
flowmete
INFL Q
Q
Q 

)
( 2
2
2
1 R
R
V 
 

22. Calculation of inflow based on level recovery
in the production casing
 Fluid inflow from formation after ESP system shutdown
should be determined after fluid discharge from the tubing
(in case of leaking or missing check valve).
 Time of fluid discharge form the tubing (in case of leaking
check valve) can be determined by backspin rotation
which is determined at the switchboard.
 Continuous monitoring of the inflow from formation during
ESP operation and shutdown for cooling allows to reduce
start-up and commissioning time and to avoid
unreasonable ESP startups and shutdowns which reduce
ESP run life.

23. Final stage of the procedure
 The well is considered commissioned when flow
rate and dynamic level have been stable for 6
hours, this time period may vary depending on
well conditions, ESP size and completion,
problemds during start-up, etc. Another criterion
to commission the well is equal casing pressure
and manifold pressure (Рcasing = Рmanifold),
which is applicable for most of the wells.

24. Specific features for
commissioning
procedure using a VSD

25. - Pump capacity
- Pump head
- Power requirements for
the pump
- Effective power of the motor










50
50
f
Q
Q








50
2
50
f
H
H










50
50
f
P
P








50
3
50
f
W
W

26. For example: under 50 Hertz the pump consumes 55 kW, if the well is to
operate only under 50 Hertz, we select 63 kW motor.
If the pump is to operate under 60 Hertz, the results will be as follows:
under 50 Hertz the power consumption of the pump is 55 kW, under 60
Hertz it is:
Therefore, if the pump is to operate under 60 Hertz, it will need a higher
power of 90 kW.
1
3
1
2
2 pump
pump Р
F
F
Р 








kW
Рpump 95
55
50
60
3
2 







kW
Р
F
F
Р mot
mot 108
90
50
60
1
1
2
2 

















27. Start-up and commissioning of ESPs equipped
with downhole sensors
 When starting the well after a workover with Рcasing = 0
atm., it is difficult to determine exactly Нstat and Нdyn. If
we have intake pressure data, we can calculate Нstat and
change of Нdyn more precisely. Pump intake pressure can
be converted to meters of fluid column by the following
formula:
SUBMERS
depth
setting
STAT
DYN Н
L
Н 
 _
)
(
 
fluid
Рcons
Рsens
Нsubmers

10




28. Advantages of VSD compared to switchboard
during seizure troubleshooting
 During ESP operation, VSD has a number of considerable
advantages compared to switchboard. These advantages
can be clearly demonstrated during ESP startup and
during wedging of seizure.
 The main advantage of VSD over switchboard both in
normal ESP operation and during wedging of seizure is
that VSD allows soft start of the unit. With the switchboard
the motor during startup receives the voltage preset at the
transformer.

29. Firstly, in this case, there is a high probability of motor,
seal or pump shaft fracture, especially if during wedging
the voltage at the transformer is increased additionally.
The result failure due to lack of fluid flow. Secondly, if
motor shaft doesn’t move during start-up, all of the power
supplied from the surface intended to generate torque
goes to heating the motor winding and submersible cable.
After a number of trials within a short period, this becomes
the key reason for reduced insulation of ‘cable-motor’
assemble and hence, ‘R-0’ failure during seizure wedging.
VSD allows to perform starting from 0-10 Hertz, therefore,
the voltage supplied to the motor is also lower. As a
result , the motor and the cable experience less heating.
During startup of the unit the maximum torque is
generated in the first 0.1-1 second. If the seizure is not
wedging at this moment, the supplied power is used for
heating during the remaining time till overload protection
actuation.

30.  Another advantage of VSD over switchboard is opportunity to
change rotation gradually without ESP shutdown (to avoid shaft fracture
and slips of seal shafts) and application of various ejective methods of
seizure troubleshooting. Rational application of these VSD functions
combined with methods of wedging seizure described above
considerably increases possibility of wedging ESP seizure.
 A competent approach to seizure troubleshooting using a VSD
allows to avoid shaft fracture, motor and cable overheating and
increases possibility of wedging compared to ESPs wth switchboard.
 Often, to wedging seizure we can use flushing (direct/(squeeze
treatment) and reverse) by crude oil with solids or by formation water
with scale. This causes deterioration of reservoir performance and killing
of the well. Preparation for flushing takes 1 to 5 hours. Application of
VSD allows to restart the unit without special tools, machines and no
waste of time. Wedging ESP seizure using a VSD should be performed
by competent personnel with enough knowledge, skills and experience to
use a VSD.

31. Checking ESP operation mode
 3 days after ESP commissioning (not later than 7 days), an electrician and a
Customer’s representative check the operation mode of the ESP by
checking flow rate measurements, dynamic level, manifold, wellhead and
annulus pressure; when setting the automatic restart time take into account
the time required to discharge the fluid from the tubing (in case of the
leaking or missing check valve);
 The electrician and a Customer’s representative perform adjustment of the
switchboard protections based on Нd, flow rate and operating current. The
electrician selects the optimum motor voltage by adjusting transformer taps
or changing the base frequency or base frequency voltage, and checks the
ESP insulation resistance.
 After that, based on achieved operating current he adjusts the switchboard
protections. Minimum current is selected in order to ensure optimum load of
the motor and to reduce heat losses.
 Settings and protections made are subject to approval by the Customer.

32. ESP shutdowns
during operation

33. Reasons for shutdown
 ESP shutdown due to overload (OP) protection
 ESP shutdown due to underload
 ESP shutdown due to insulation control
protection
 Reduced (no) flow
 Electric power cut (scheduled and emergency
cases)

34. ESP shutdown by overload
protection
The reasons for overload shutdown may be
as follows:
- Seizure of pump due to plugging.
- Incorrect selection of voltage tapping.
- Penetration of formation fluid into the
motor.
- Low supply voltage
- Improper adjustment of the switchboard

35.  Make sure the following is serviceable and functioning: insulation control
protection, overload protection, insulation resistance and a ‘star’ monitoring,
serviceability of switchboard controller;
 Disconnect submersible cable form the junction box, wipe the wires dry and
strip the surface of conducts of the submersible cable, measure the
insulation resistance of ‘cable-motor’ system and ‘switchboard –vent box’
system using an ohmmeter and determine if there a ‘star’ at ‘cable-motor’,
visually check condition of the cable from the junction box to the christmas
tree (insulation melting, mechanical damage);
 Check supply voltage at the phases at the low and high voltage sides of the
step-up transformer. Make a test run of the switchboard with the ESP cable
disconnected. Check the supply voltage at the phases of the switchboard.
 If the insulation resistance exceeds 1 MOhm, proceed with the startup of the
unit. Measure the current at the phases by clamp meter at the high and low
sides of the transformer. Phase misbalance in terms of voltage and current
should not exceed 3 and 15% respectively.
 Compare the readings of the ammeter and of the switchboard controller, if
necessary adjust the readings of the controller;
 Monitor the operation mode until desired operational parameters are
achieved (flow rate, dynamic level, watercut).

36. - All start-up activities after triggering of the overload protection of the
switchboard must be recorded in the operation note of the ESP. After
overload protection of the switchboard is triggered, the equipment may be
operated cyclically (maximum 3 cycles) with the operating current
exceeding the rated value for a period which should not exceed those
specified in Table 1 ,
followed by cooling shutdown (not less than 30 minutes);
Table No.1
Submersible motor overload
against nominal value
1.1 1.2 1.3 1.4 1.5
Maximum operation time (min.) 60 10 5 2 1

37. If the load current is not reduced to the rated value, a
artificial lift engineer makes a decision about additional
activites (flushing, seizure unlock with a VSD, etc.) or ESP
pulling;
After the load current reaches the rated value or becomes
lower, make optimization of the transformer voltage and re-
adjust the overload and under-load protections;
If a decision is made to pull the ESP, shut down the unit. An
electrician will scan the data of the controller and disconnect
the cable from the junction box according to the safety
requirements.

38. ESP shutdown due to underload,
low production
The following may lead to Underload / low production
shutdown:
Gas lock.
Tubing plugging with paraffin.
Tubing leak.
Plugging of the choke at the christmas tree.
Low dynamic level.
Pump wear
Shaft fracture

39. • Disconnect the submersible cable from the junction box.
Check correctness and functioning of underload protection
without downhole equipment;
• Check the supply voltage at the phases at the low and high
sides of the transformer;
• Check the current at the phases by clamp meter at the low
and high sides of the transformer;
• Connect the unit, proceed with the startup;
• Compare the readings of the ammeter with switchboard
controller, if necessary adjust the readings of the controller;
• Check serviceability of the current and voltage meter when
reaching the working value of the dynamic level;
• Check pressure generated by the pump with the closed
manifold valve. Not more than 60 atm.;

40.  Check the measurement results for compliance with
head capacity curve of the particular ESP series;
 Check the tubing for paraffin;
 In case of low or zero production, make reverse flushing
through the pump with the simultaneous startup of the
ESP (by water or inhibitor solution to remove the
paraffin, if the equipment permits), in case of parrafins in
the tubing, use hot oil (temperature not more than 80 С);
 Once the reason of underload is determined, the
electrician should read out the database from the
controller. Electrician and production engineer make a
decision about further ESP operation (with adjusted
switchboard/VSD settings), or ESP pulling.

41. ESP shutdown due to insulation
control protection
Poor insulation may be caused by:
 Penetration of formation fluid into the motor.
 Submersible cable crush.
 Surface cable crush.
 Faulty insulation control unit.
 Insulation deterioration in the input at the tubing adaptor.

42.  Check serviceability and functioning of the insulation control, overload
protection, underload protection;
 Disconnect submersible cable form the junction box, wipe the wires dry and
strip the surface of conducts of the submersible cable, measure the insulation
resistance of ‘cable-motor’ system and ‘switchboard –vent box’ assembly using
an ohmmeter and determine if there a ‘star’ at ‘cable-motor’, visually check
condition of the cable from the junction box to the switchboard (melting,
mechanical damage, burn);
 When there are no problems (‘star’ available at ‘cable-motor’, insulation of
‘cable-motor’ and ‘switchboard-junction box’ is more than 1 MOhm, no melting,
mechanical damage of the cable on the surface), repeat ESP startup;
 When there are problems revealed (‘star’ is not available at ‘cable-motor’,
insulation of ‘cable-motor’ and ‘switchboard-vent box’ is 1 MOhm or less,
melting, mechanical damage of the cable on the surface) inform the production
department. Further operation should be controlled by the production
department;
 Decision to start-up ESP with the switched off insulation control system may be
taken only upon approval from the artificial lift engineer and requires re-
adjustment of the fast-response overload protection from the operating current;
 Record in detail the results of the works performed in the operations note and
operations log.

43. Electric power cut
(scheduled and emergency)
 Startup the ESP system at the minimum frequency
(depending on the fluid level in the annulus) with the
compulsory adjustment of under-load protection;

 Based on startup results, make a decision to increase
ESP frequency to the previous operating level (before
the shutdown);
 After the ESP reaches the frequency used before the
shutdown, make the decision on further frequency
increase based on the operating parameters with the
voltage optimization through changed basic frequency
and adjusted under-load protection.

44. Unlocking ESP seizure by
special machines
 The idea is to flush the ESP system by a fluid involving special
machines.

 The flushing may be direct (through tubing) and reverse (through
annulus). If the tubing is not equipped with a check valve (as a rule, in
case of high performance ESPs) or the check valve is leaking, make
direct ESP flushing through tubing. In other cases make a reverse
flushing through the annulus.

 In ESP –produced wells the annulus fluid level is normally low. To
create circulation through the unit in case of reverse flushing, we need
fluid volume comparable to the kill fluid volume (~15m3). Reverse
flushing is not feasible in wells where formation consumes fluid during
reverse flushing, because it is impossible to create circulation in this
case.

45. Procedure:
 Electrician increases voltage at the transformer (switch over tappings by three
to five taps to increase the voltage). If necessary, replace surface electric
equipment.
 Operator closes the annulus valve;
 Prepare the injection line depending on the type of flushing (direct, reverse),
connect the line to wellhead or annulus;
Direct flushing:
 - inject at least 10-15 m3 of fluid into the tubing, stop flushing, close wellhead
valve, startup the unit in reverse (for ESPs with a motor of up to 63 kW
inclusive), if the ESP motor is more than 63 kW, the decision about startup in
reverse should be made by the production department;
 - if the unit is successfully started, leave it running for 10-15minutes, after that
change to direct rotation.
 - if the unit is successfully started in direct rotation, leave it running, keep
monitoring the well operation till the flow is stabilized to ensure proper cooling of
the motor.
 - if the operating current did not reduce during reverse
 rotation (Iw>Inom), even after voltage increase, or the unit could not be started
in direct rotation after reverse rotation, shutdown the unit to cool it down for at
least 1 hour, then repeat the cycle of the operations (not more than 3 cycles).

46. Thank you
for your attention
Questions are
welcome