Hitachi Drives Frequently Asked Questions
Use "Ctrl-F" to search for specific words in this FAQ.
Question:
How do I connect a resistor (SRB) to an inverter drive?
Answer
Connect the resistor leads to "+" and "RB." There are also a set of "overtemperature" contact terminals on the resistor which should be wired to an intelligent input allocated for "trip" purpose. It would also be appropriate to wire any emergency stop contacts in series with this overtemperature contact.
FAQ ID: 272
Question:
How does Hz correlate to speed on an inverter drive?
Answer
Motor base speed divided by 60 Hz = RPM/Hz. Example; 1200RPM divided by 60 = 20 rpm/Hz. This information is useful for scaling the inverter display to display rpm's instead of Hz. Simply place the above result into B86 and then choose D07 to display. The display will read 0 - 1200 rpm.
FAQ ID: 273
Question:
Do I need to purchase anything else to program my drive?
Answer
No, you can program the drives from the front panel using the function keys and by using the appropriate parameters located in the manual.
FAQ ID: 274
Question:
Can the software be used with Allen-Bradley equipment?
Answer
No, the DOP software cannot be used with the Allen-Bradley equipment due to the function blocks capability of the Allen-Bradley equipment.
FAQ ID: 276
Question:
I cannot get my intelligent terminal to program with the options I want. It just skips over them. Why?
Answer
If the option you wish to use is default of a different terminal the inverter will not let you program it in two places. You will need to use it at its default location or change it so that you do not have it in two places. Also, if the drive is in Run, items such as Intelligent Terminal Allocation cannot be changed due to safety reasons.
FAQ ID: 278
Question:
Can I use the 24vdc supply on the inverter for field devices on my machine?
Answer
The 24vdc supply on the inverter is for the operation of control terminals and is not recommended for use with other devices.
FAQ ID: 279
Question:
Will the SJ-100 accept encoder feedback?
Answer
No, the SJ-100 will not accept encoder feedback. It is a micro drive and does not have the option card, and therefore no encoder feedback.
FAQ ID: 280
Question:
We are building a panel for our drives. How can we know the heat put out by each drive?
Answer
This watt loss chart shows the amount of heat generated by the drive at 70 and 100 percent load of drive. The units are given in watts lost.
FAQ ID: 282
Question:
Although the SJ100 inverter is a variable speed drive, can I use it in a fixed-speed application?
Answer
A fixed speed application usually is a result of cost-sensitivity or negligible benefits if variable speed were used (consumer products are examples). In those cases, the power source connects directly to the motor (no special drive needed). However, using a variable speed drive can benefit many type of industrial and commercial motor applications, by providing controlled acceleration and deceleration, high torque at low speeds, and energy savings over alternative solutions.
FAQ ID: 285
Question:
Can I use an inverter and AC induction motor in a positioning application?
Answer
That depends on the required precision, and the slowest speed the motor will must turn and still deliver torque. The SJ100 inverter will deliver full torque while turning the motor at only 0.5 Hz (15 RPM). DO NOT use an inverter if you need the motor to stop and hold the load position without the aid of a mechanical brake (use a servo or stepper motion control system).
FAQ ID: 286
Question:
Why does the manual or other documentation use terminology such as "200V class" instead of naming the actual voltage, such as "230 VAC?"
Answer
A specific inverter model is set at the factory to work across a voltage range particular to the destination country for that model. The model specifications are on the label on the side of the inverter. A European 200V class inverter ("EU" marking) has different parameter settings than a USA 200V class inverter ("US" marking). The initialization procedure can set up the inverter for European or US commercial voltage ranges.
FAQ ID: 288
Question:
I live in a country where the domestic utility power is 115 VAC. Is there a way to conveniently access a 230 VAC power source for a test bench to develop a motor application?
Answer
A 1:2 step-up transformer is available from a number of sources (check your local electrical supply house). The transformer will be designed to develop 230 VAC from 115 VAC, for example. Be sure the power output rating (kW) of the transformer is greater than 1.73 times the three-phase current of the motor you intend to power. We recommend doing this for motors 1/2 horse-power or smaller, with small loads. For 400 V class inverters, we recommend only using a utility power source of the correct voltage.
FAQ ID: 290
Question:
Some models of Hitachi inverters will accept either single phase or three-phase power input. How do I know which input power type to use? Can the drive power a single phase motor?
Answer
If three-phase power is conveniently available for your application, we recommend using that (the inverter can develop its three-phase output power most efficiently from three-phase input power). In the absence of three-phase power, you can use a single-phase power source with slightly less efficiency but the power output rating is the same for N models (single or three-phase).
All Hitachi inverters develop a variable three-phase output, requiring the use of a three-phase AC induction motors.
Sizing single phase drives:
1) Higher motor current for single vs. 3 phase - this is about double (x 1.732 to be exact, but double for selection purposes). You must also account for peak motor current (application dependent), and select the proper drive size based on its output current capacity, rather than hp rating.
2) The fact that one input phase is missing means that part of the input bridge is carrying higher current than it normally would. You must make sure that the input current does not exceed the rating of the drive.
3) Since we are only rectifying single phase, the harmonic content is higher, and different in frequency composition. This means that an input line reactor is a definite requirement. Also this impacts on the DC Link, and the higher harmonic content may adversely affect the life expectancy of the DC Link capacitors. There is no easy way to calculate this, but if the drive is sized adequately, this is not a major issue.
Standard practice is to double the size of a 3-phase rated SJ300 drive when using single-phase input. Connect power (L1)to "R" and (L2) to "T" terminal, and jumper "S" and "T" together. Under no circumstances can the output be used on a single-phase motor.
FAQ ID: 291
Question:
Will I be able to add dynamic (resistive) braking to my Hitachi SJ100 drive after the initial installation?
Answer
Yes. The SJ100 inverter already has a dynamic braking circuit built in. Just add the resistor sized to meet the braking requirements.
FAQ ID: 297
Question:
Several options related to electrical noise suppression are available for the Hitachi inverters. How can I know if my application will require any of these options?
Answer
The purpose of these noise filters is to reduce the inverter electrical noise so the operation of nearby electrical devices is not affected. Some applications are governed by particular regulatory agencies, and noise suppression is mandatory. In those cases, the inverter must have the corresponding noise filter installed. Other applications may not need noise suppression, unless you notice electrical interference with the operation of other devices.
FAQ ID: 299
Question:
The SJ100 features a PID loop feature. PID loops are usually associated with chemical processes, heating, or process industries in general. How could the PID loop feature be useful in my application?
Answer
You will need to determine which main variable in your application the motor affects. That is the process variable (PV) for the motor. Over time, a faster motor speed will cause a faster change in the PV than a slow motor speed will. By using the PID loop feature, the inverter commands the motor to run at the optimal speed required to maintain the PV at the desired value for current conditions. Using the PID loop feature will require an additional sensor and other wiring, and is considered an advanced application.
FAQ ID: 300
Question:
What is the proper selection of line reactors for single phase 230 V inverters?
Answer
View this 1-PHASE Line Reactor Application Matrix.
FAQ ID: 301
Question:
What are the dimensions of the OPE-J?
Answer
2 7/8” H X 3 3/16” W X 5/8” D (not including mounting tabs or connector)
FAQ ID: 621
Question:
The display on my drive reads E12 and will not allow me to program or run the drive?
Answer
One of the input terminals is configured for an external trip with the corresponding function set to NC. This configuration is common for e-stop circuits and remote trips such as over-pressure, and over-temperature watchdog relays. The circuit must be complete, with the physical NC contact in series with P24 (CM1 on the SJ300) and the assigned terminal associated with the external trip.
If this was not the intent, the terminal with the external trip assignment must be jumpered to P24 (CM1 on the SJ300) completing the circuit. Reset the drive by the Stop/reset button or by cycling power (if cycling power, remember to allow a few minutes for the drive to discharge before turning power back on.) Commence changing parameters to the desired settings.
FAQ ID: 743
Question:
No matter what I change on the SJ100 or L100 I cannot get the remote operator to start/stop or change speeds, why?
Answer
Depress the MON button until you see F/R SELECT or F-SET SELECT, use the one arrow to position cursor on right hand side. When positioned, arrow up or down until you see REM. When parameter is changed, depress the STR button to make the change permanent. Changing both function listings to REM will allow you to operate remotely. Depress the FUN and then the MON buttons to get back to the FS 000.0 0.0Hz display. The FWD RUN and REV RUN buttons should now be active as well as changing FS to desired speed.
FAQ ID: 746
Question:
What size remote potentiometer do I use?
Answer
1-2 k ohms 2 W.
FAQ ID: 749
Question:
How can I digitally control speed on the keypad with the up and down arrows instead of using the local potentiometer?
Answer
Change parameter A01 to 02 (internal parameter.) Instead of going back to D01 for frequency display, go to F01 and hit the function key. After run is enabled, the speed can be adjusted up and down with the arrows.
FAQ ID: 768
Question:
Is there a difference between the way drives are defined as sinking or sourcing devices versus PLCs?
Answer
Yes, the big difference is drives are classified as the devices that they connect too, where as PLCs are classified as the device itself. It’s a little confusing, but allow us to elaborate on discrete inputs:
SJ300 is defaulted as sinking, so it connects to sinking devices. If you wanted to control multi-speeds with a dc output card instead of a relay card, it must be sinking in nature. The SJ300 is the only drive that can be changed to sourcing. Change the jumper between P24 and PLC (default) to PLC and CM1. You can now connect it to a sourcing card.
L100 and SJ100 are classified as sourcing devices, so they only connect to sourcing cards.
Special Note: All analog inputs (0-10vdc and 4-20ma) must be sourcing in nature.
FAQ ID: 769
Question:
How does the jog command work?
Answer
The forward run or reverse run enable contact must first be made, then the jog contact can be closed to initialize the jog function. While in jog mode all other speed control is suspended. To clear the jog function, the run enable must be broken. Once cleared the drive can resume normal operation.
FAQ ID: 770
Question:
What parameters do I change in the L100/SJ100 drives for a centrifugal load?
Answer
1. A41
2. A44
3. A82
4. B02
5. B12
6. B13
7. B88
8. F02
9. F03
FAQ ID: 776
Question:
What parameters do I change in the SJ300 drives for a centrifugal load?
Answer
1. A041
2. A044
3. A082
4. B002
5. B012
6. B013
7. B088
8. F002
9. F003
FAQ ID: 777
Question:
How do I size a SJ300 drive for the 0Hz function?
Answer
With this function the drive produces 200% torque on start up. The drive must be derated by one drive size. If it is not, the drive will trip out on over current.
FAQ ID: 778
Question:
On the SJ100/L100 when I run multi-speeds, do I need to set A20?
Answer
A20 can be considered multi-speed 0, If A01 is set to 02 (internal parameter) the frequency setting will be reached at the initialization of the run enable. E.G. I want the drive to hit 50Hz as soon as the fwd terminal is closed and all other multi-speed terminals are open.
If A01 is set to 01 (terminal) A20 becomes invisible. The first multi-speed will be reached after the fwd is enabled and the terminal assigned to Multi-speed 01 is closed. E.G. I want the drive to be at 0Hz when the fwd terminal is closed and all the other terminals are open. I want the drive to hit 50Hz when both fwd and terminal (multi-speed 1) are closed and all the other terminals are open.
Another look:
Reaction:
o Drive to X Hz at run enable.
Settings:
o A01
o A20
o A02
Inputs:
o Run enable on local Keypad or Run terminal
Reaction:
o Drive to 0 Hz at run enable
o Drive to X Hz at Multi-speed 1 enable
Settings:
o A01
o A20
o A21
o A02
Inputs:
o Run enable from run terminal
o Multi-speed enable from multi-speed terminal
FAQ ID: 803
Question:
What considerations do I need to investigate for running multiple motors on one inverter?
Answer
Please review the following:
Speed reference – all motors must be run at the same speed. They have the same frequency and voltage.
Inverter Size – the size must be based on total current and not HP. If the aggregate is close, always round up.
Motor Protection – an output line reactor and manual motor starters functioning as thermal motor protectors on each motor branch.
FAQ ID: 805
Question:
What considerations do I need to investigate to run the motor beyond 60Hz?
Answer
You must understand the basic volts per Hertz relationship. When the frequency is raised to it’s base frequency of 60Hz (for this example, your base frequency can be changed,) your voltage is equal to maximum output voltage 460 VAC (also for this example.) At this point, the motor is maximum output on voltage, but you can increase your frequency and overdrive the motor. Since the drive cannot increase voltage to maintain a constant ratio, torque is eroded by inverse relation to frequency. You can estimate your torque relationship by the following formula:
Max speed is 75 Hz, Base speed is 60Hz
T max = T base x (ratio of base/max)
T max = 100% x (60/75)
T max = 80%
The maximum amount of torque available at 75Hz is 80%.
Some considerations:
A TENV motor is always a good idea when overdriving, no fan means less drag on motor, increasing torque a marginal amout.
Contact the motor manufacturer to verify that the motor can handle being overdriven both electrically and mechanically (bearings.)
FAQ ID: 815
Question:
Can I duplicate MOP (Motor operated potentiometer) or MOR ( Motor operated rheostat) with the intelligent inputs.
Answer
SJ100/SJ300 set inputs to #27 up reference and #28 down reference. The L100 drive does not have this capability.
FAQ ID: 830
Question:
What is the bit resolution of Hitachi drives?
Answer
L100/SJ100: input (O & OI) 10 bits; Output (FM) 8 bits. SJ300: input ( O, OI, O2) 12 bits; output 8 bits.
FAQ ID: 833
Question:
I cant get the knockouts out of the bottom of the SJ300 drive or the NEMA 1 cover on the L100/SJ100?
Answer
A suggestion would be to drill a self-tapping screw into the knockout and use a pair of diagonal cutters as a lever.
FAQ ID: 868
Question:
Can I use the free-run stop function on the L100 drive?
Answer
Yes you can, but the FRS must be engaged from a programmed intelligent terminal (address #11.) The SJ100 has the ability to set B91 to FRS or to use the intelligent terminals the same way.
FAQ ID: 876
Question:
What does the temperature spec of the drive mean? What is the conversion from Celsius to Fahrenheit?
Answer
The spec is –10*C to 50*C.
When the operating temperature is between 40*C and 50*C the following events must happen.
1.) The carrier frequency must be reduced to 2.1 kHz
2.) The output must be derated to 80%
3.) The top cover of the drive must be removed (this also nullifies the NEMA rating of the drive)
The conversion from Celsius to Fahrenheit is: F = 1.8 x C + 32.0
FAQ ID: 879
Question:
What Type of surge protection should I use with the dc output of the drive output terminals?
Answer
TVS P6K30CAGICT-ND
Diode IN4004CT-ND
FAQ ID: 885
Question:
Can I use a motor starter protector with Variable speed drives and inverters?
Answer
They are only recommended for multiple motor applications from the output of a single drive. The drive handles the aggregate current monitoring, not the individual motor branch current.
NEC article 430 53c “group motor rating” deals with the concept of conventional across the line motor starters and the requirements of short-circuit protection from feeder to motor branch circuit. These guidelines do not mention variable speed drives. The recommendation is always to follow the manufacturer specification. In this case Hitachi recommends J class fuses.
You would never use a MSP, because it is not rated as a SSPD (short circuit protective device) in North America, in place of these J class fuses. There is also no need of an overload on the output side of the drive unless there are multiple motors being used.
Always check with your local inspectors and municipalities before an installation to verify their local requirements which may differ from the National Code.
FAQ ID: 899
Question:
Can I use these on electric vehicles?
Answer
AutomationDirect is a direct seller of automation and industrial control products such as PLCs, sensors, pushbuttons, AC drives/motors, enclosures, operator interfaces, and much more.
AutomationDirect is aware that many engineers and hobbyists are currently designing or converting vehicles from internal combustion engines to electric engines. Our current drive and motor products are intended to be used in industrial applications. As a result, AutomationDirect does not currently support or encourage the use of our products in electric vehicles. We apologize for this, and may revise this policy at a later date if more suitable equipment becomes available.
FAQ ID: 1075