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Old 30th September 2022, 20:42   #271
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While it is understandable that the Tiago motor has lower power (74 ps for LR and 60 ps for MR) vs Nexon Prime (129 ps) vs Nexon Max (143 ps)

Kerb weight of Nexon Primw is 1400 kg. What is the kerb weight of Tiago LR?

That should get us some sense of the power to weight ratio.

If it is 1.2 ton as called out by man_and_machine then the nimbleness could be a concern.

Pendulum is swaying again (4th time since launch)

In contrast the lowest spec Tesla model 3 is just 283 ps and about 1600 kg.

Last edited by Turbanator : 30th September 2022 at 21:29. Reason: posts merged
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Old 30th September 2022, 20:43   #272
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Re: Tata Motors announces Tiago EV. EDIT: Launched at Rs. 8.49 lakh; offers 315 km range

Quote:
Originally Posted by sumannandy View Post
Does Tiago EV support charging from 50 KW DC Charger? Or is it limited to max 25 KW DC Charger.
I don't think Tata discloses this anywhere but a 10-80 top up of 57 mins on DC charging means its charges at much lower than 25kW most of the time. I am guess for the 19.2kW 24-25 might be the peak and for 24kW it just might be slightly higher.

People with premium EVs and MG ZS owners are doomed to wait for Tata's people mover hogging fast chargers anyway.

This does makes me wonder, while this car is solely meant to be a city car, the low range and the slowish charging would mean, it can't really be the only car one has.
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Old 30th September 2022, 21:37   #273
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Re: Tata Motors announces Tiago EV. EDIT: Launched at Rs. 8.49 lakh; offers 315 km range

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Originally Posted by man_and_machine View Post
Exactly the right point. How does the car feel drive in the 30 - 70 band, is characterised by the motor output, and my point too. the 45 PS motor, lugging 1.2 tons on a 19 kWh battery with shorter ranges and charge cycles is why it might be a package too cut to the bone to give a useful experience. At that sticker price, is that a good experiment? Its not expensive an experiment on manufacturing, as the part bin can be fully repurposed. But on first time EV buyers at the entry level, you want it to be a Santro that rings the right bells not something that is short of it. 10L is not cheap, would you buy one just because it's a cheap EV or because it's the right one. I have my doubts.
Thanks for your efforts, finally able to appreciate your perspective, after studying a bit more about the torque characteristics of a PMS motor. Indeed, the acceleration at higher speeds with a weak motor and so much kerb weight is a solid concern and it should be thoroughly checked before a decision is taken.

I am starting to have a feeling that highway maneuvers could be a good struggle, but city driving should be decent.

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Even Tesla which has motor at least 4 times more powerful than Tiago starts losing torque rapidly after 40 mph.

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Last edited by ajayc123 : 30th September 2022 at 21:58.
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Old 30th September 2022, 23:20   #274
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Re: Tata Motors announces Tiago EV. EDIT: Launched at Rs. 8.49 lakh; offers 315 km range

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Originally Posted by ajayc123 View Post
Thanks for your efforts, finally able to appreciate your perspective, after studying a bit more about the torque characteristics of a PMS motor. Indeed, the acceleration at higher speeds with a weak motor and so much kerb weight is a solid concern and it should be thoroughly checked before a decision is taken.

I am starting to have a feeling that highway maneuvers could be a good struggle, but city driving should be decent.
Thank you, finally a non-popular, non-euphoric view sees the light of the day.

EVs are still nascent in India. 99% of the people still don't understand anything about it. The first experiences need to convince them that these are really usable machines, do all their older counterparts did, maybe even more. The adoption will naturally hold ground. Today, the USP is just cheaper than petrol/diesel. Nothing much about how they feel as a first (or second car) in the house is well established or understood.

Vanity metrics like 0 - 60 get more attention than things like smooth gearless drive or silent low NVH travel. Cost of the EVs is defiantly why people still feel its novelty. Bringing down cost is surely the next step, that should be done via better cost management of input cost viz.manufacturing, supply chain and innovation of the critical parts like battery tech. Just speccing it down might spoil the over all usability and long term acceptability.

But, again, I want to be proven wrong and somehow TATA has cracked the bracket for affordable EVs, helps the whole segment. This one is not so convincing. May be our solid T-Bhp TD review will throw more light.
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Old 30th September 2022, 23:44   #275
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Re: Tata Motors announces Tiago EV. EDIT: Launched at Rs. 8.49 lakh; offers 315 km range

Another interesting thing that I notice is that erroneously or conveniently some things are missed. For example, on the Tata EV portal, the kerb weight of EV Prime is mentioned as 1400 kg, but missing for the EV max. Likewise, I couldn't find the kerb weight of Tiago so far.

For the Tiago, the 0-60 kmph in 5.7s has been mentioned as a solid marketing point, but it rings a bell why the 0-100 kmpl has been missed for Tiago, even though for Nexon, it is marketed as 9 seconds ( does it not look good? Is it even achievable? What is the max speed? I would love to know answers to these in the TBHP review).

I sense it should be a good city car, but we should know full capabilities for a suitable decision.

Last edited by ajayc123 : 1st October 2022 at 00:07.
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Old 1st October 2022, 00:36   #276
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Re: Tata Motors announces Tiago EV. EDIT: Launched at Rs. 8.49 lakh; offers 315 km range

We went ahead and pre-booked the Tiago EV XZ+ Tech Lux variant to replace my dad’s 8 year old Vento 1.6 TDi. My dad is 60+ and his running has significantly reduced and he is finding it difficult to drive the diesel manual car. We were on the lookout for a convenient car for him for quite some time and ended up booking this. This would be a city only car in the family that anyone in the house could drive with almost negligible running and maintenance cost. Slightly scared of TATA’s ASS but hope everything turns out well.
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Old 1st October 2022, 01:16   #277
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Re: Tata Motors announces Tiago EV. EDIT: Launched at Rs. 8.49 lakh; offers 315 km range

[Warning - long, tech read, continuation of spec data based analysis]

This could be hunkering down the rabbit hole of the spec speculation (pun intended), I am really curious on what TATA could have done to make this seemingly impossible physics happen.

This team-bhp homepage thread on Atto 3 serves as a good reference point.

https://www.team-bhp.com/news/byd-at...hscreen-teased

The Atto 3 is an established car, has real life users, been around and had once even for short period of time outsold the Tesla (when Tesla had a small supply chain hiccup).

In the summary of the thread take a look at the spec.

"Powering the Atto 3 is a permanent magnet synchronous motor that develops 201 BHP and 310 Nm, which is said to propel the car from 0-100 km/h in 7.3 seconds. It is rumoured to come with the larger 60.48 kWh battery pack, which has a maximum claimed range of 420 km (WLTP cycle)."

In contrast, we are looking at 45 ps (bhp numbers are a close good approximation), 110 Nm, 0 - 160 5.7s, ˜20 kWh and ˜250 km.

Weight of Atto 1750, Tigor ˜1200.

If we establish the Atto 3 baseline, and fit that to the downgraded spec and see what variables need to be tweaked to get the tigor numbers.

we all know f = ma. Or force is mass times accelaration. So if we hold the acceleration constant then lesser force is needed to move the same mass or, if the mass is reduced the force needed moves south.

Both the acceleration and force move linearly, until the torque drops. Or as long as the torque is flat or even linearly moving all other parameters move along a linear path driven by y = mx + c (where y is the acceleration point, m is slope of the acceleration graph, x is the rpm and c is the offset from the starting of the acceleration. For a car that starts from idle on a 0 - 60, c = 0) So, its y = mx.

What this helps is to establish the following,
1. We can vary the torque and see what the new 0 - 60 can be
2. Vary the power and see what the numbers are
3. vary the gross weight (which is mass x g where g is 9.8/s square, but its a constant so we can ignore it) and see what the numbers are
4. vary more than one parameter and see how the final numbers should be

From a what should be, to what is, identify what are the other variables that can be changed. In this case, it could be a different drive or gear ratio at different rpm/torque levels or different ampere or current drawn levels to make this graph non-linear, i.e changing the power characteristics of the motor. Since this is a PMS motor you can't vary the power characteristics of the rotor you can only control the flux on the casing.

1. Match the weight
Starting at the Atto baseline, if we lighten the car from 1750 to 1200 all other params being the same the 0 - 100 would be 5.00s

2. Match 0 - 60 spec
Now we get to 0 - 60 (still the flat torque range for idle start) is 3.00s

3. Match torque
Now we get to the 110 Nm, the 0 - 60 will e 8.45s. However, the spec says 5.7s which is 48% deviation. So we have to now introduce a variable here, else the physics will fail. It can be one or a combo of the following (A) change the current characterstics (B) change gear ratio dynamically/electronically at different rotor rpm values (C)some innovatite engg technique that is not pubically known.
Both A and B will lead to a higher battery drain or amphere flow so the claimed range on WLTP cycle is not possible.

Now, we look at more realistic 30% start to stop, 70% 30 - 70km cycle, city like drive. Let first convert the bhp and kw into a single UoM so its easy to understand. 1 BHP ˜= 0.75 kw.
So the ATTO 3 has a 60.kwh or 81 bhpHour battery.
Tigor has 20 kwH or ˜27 bhpHour battery.

f = m X a (we revisit this)
So if both cars are doing the same city like drives (and lets assume thier ranges are defined so) so the 'a' is constant (we still have to figure out how that 'a' is same with that huge 48% gap, let's assume its happening somehow)

Total force applied (or in other words drawn from a source a.k.a the battery over constant time, which is the definition of kwh or our new metric bhpHour) the mass or m matters. 1200 kg (removing constant g) is 70% of 1750 kg, so if they both had the same source strenght or kwh, the rage should be atleast 30% (100 - 70) more. Which is 450 * 1.3 = 585 km. Since we have 27 bhpHour and not 81, we should be looking at 195 km v/s 250(a little close to spec), but at 30% the torque levels (110 v/s 310 Nm), again there is some variable which is difficult to explain. Unless the battery tech is something innovative (atlest its not claimed)

Its seems to be tuned to juice out a usable city range extremly senstive to speed, drive style, start-stops, temperature, gross load (every passenger might start to matter), gradient, cruise time, over all friction (hence 65/ r14) etc.

One does not want so much variability. All this matters when you are eaking out every ounce since you are running close to rated spec on all parameters majority of the time.

I am reminded of an analogy (a far shot but drives the pattern), while Apple had stuck to 12 MP camera until 2020 on a 599$ phone and the world was flooded with 50, even 100 MP at less than 100$ phones, the outcomes were so very different. In a skewed feature to price ratio in the absence of disruptive input, the compromises are not always apparent. I am usully a little vary of "itna zyda itne mai" campaigns.

Often the whole is more than sum of parts, and finally how the car might be put together might trash all these assumptions. Knowing that there are no innovatively engineered parts either on the drive train or the battery how could this have been made? I am not negative on this launch, I am just not able to get euphoric on it.
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Old 1st October 2022, 01:46   #278
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Re: Tata Motors announces Tiago EV. EDIT: Launched at Rs. 8.49 lakh; offers 315 km range

Quote:
Originally Posted by man_and_machine View Post
[


"Powering the Atto 3 is a permanent magnet synchronous motor that develops 201 BHP and 310 Nm, which is said to propel the car from 0-100 km/h in 7.3 seconds. It is rumoured to come with the larger 60.48 kWh battery pack, which has a maximum claimed range of 420 km (WLTP cycle)."

In contrast, we are looking at 45 ps (bhp numbers are a close good approximation), 110 Nm, 0 - 160 5.7s, ˜20 kWh and ˜250 km.

Weight of Atto 1750, Tigor ˜1200.

If we establish the Atto 3 baseline, and fit that to the downgraded spec and see what variables need to be tweaked to get the tigor numbers.
First of all, The Tigor comes with a 75ps ( 72hp ) motor. It does 0-60 in around 6 seconds and 0-100 in 12.5 seconds which is nothing crazy but not slow either. And you don't need to go crazy with overly simplified 10th grade maths to calculate it either. Here is a video:



Electric motors have much better initial acceleration due to torque availability from 0 rpm and considering this will be most people's city car, this will have more than enough power to leave comparable spec cars like the i20, swift, Baleno etc behind from a standstill as long as you are not on a highway. The Tiago will be slightly lighter than the Tigor (because physics) and thus will do slightly better in acceleration too. All claimed ranges for both EVs and ICE cars in India are best taken with a grain of salt so again let's look at the Tigor EV's range as reported by owners here which is around 200-250kms. We can assume to get the same here.
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Old 1st October 2022, 02:09   #279
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Re: Tata Motors announces Tiago EV. EDIT: Launched at Rs. 8.49 lakh; offers 315 km range

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Originally Posted by Cresterk View Post
First of all, The Tigor comes with a 75ps ( 72hp ) motor. I..... And you don't need to go crazy with overly simplified 10th grade maths to calculate it either. .
Oh, sorry I see where the confusion is coming from. So similar sounding names, I will correct it, I am referring to the new 8.45L entry level model with a very similar name (and url) which is this,

https://tiagoev.tatamotors.com/features/

v/s the tigorev, which is a different model (already in the market, not qualms there)

https://tigorev.tatamotors.com/featues at a very different price point.

I recall, someone sharing in confusion on the same thread too. Did not see that until I looked at the urls.
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Old 1st October 2022, 02:19   #280
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Re: Tata Motors announces Tiago EV. EDIT: Launched at Rs. 8.49 lakh; offers 315 km range

Please read corrected the incorrect references to Tigor as Tiago.
Quote:
Originally Posted by man_and_machine View Post

Weight .. (Tigor -> Tiago)˜1200.

.... see what variables need to be tweaked to get the (tigor -> Tiago) numbers.
.....
(Tigor -> Tiago) has 20 kwH or ˜27 bhpHour battery.
Making edits, sorry for the confusion folks, I had draft on 2 comparios and the similar names got me to confuse (and also irritate) a bunch of you folks.
I am referring to the Tiago.ev, on this url here,
https://tiagoev.tatamotors.com/features/
and not the Tigor EV, on this url here,
https://tigorev.tatamotors.com
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Old 1st October 2022, 05:56   #281
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Re: Tata Motors announces Tiago EV. EDIT: Launched at Rs. 8.49 lakh; offers 315 km range

Quote:
Originally Posted by Cresterk View Post
First of all, The Tigor comes with a 75ps ( 72hp ) motor. It does 0-60 in around 6 seconds and 0-100 in 12.5 seconds which is nothing crazy but not slow either.

Electric motors have much better initial acceleration due to torque availability from 0 rpm and considering this will be most people's city car, this will have more than enough power to leave comparable spec cars like the i20, swift, Baleno etc behind from a standstill as long as you are not on a highway. The Tiago will be slightly lighter than the Tigor (because physics) and thus will do slightly better in acceleration too. All claimed ranges for both EVs and ICE cars in India are best taken with a grain of salt so again let's look at the Tigor EV's range as reported by owners here which is around 200-250kms. We can assume to get the same here.
Thanks. This is useful, and for the LR models we should expect a performance comparable to Tigor that has 75 ps motor, which appears to be a reasonable package that does the job.
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Old 1st October 2022, 08:28   #282
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Re: Tata Motors announces Tiago EV. EDIT: Launched at Rs. 8.49 lakh; offers 315 km range

Quote:
Originally Posted by XRoader_001 View Post
Sharing Key Specifications of Tiago.ev :
Referring to this spec sheet


Quote:
Originally Posted by man_and_machine View Post
In contrast, we are looking at 45 ps
Dear friend, you seem to be fixated on this power figure. But it is the wrong number.

The brochure mentions power output of the base variant as 45Kw and not 45 Ps.

45Kw = 60 Ps.
Can you please redo all the calculations with the new power figure? I didn't bother reading since all of it was based off a wrong assumption.


Anyways, before you do the calculations and without bringing the 3x priced BYD Atto 3 into this, moving on to acceleration. The spec sheet mentions 0-60 time as 6.2 seconds.

For comparison, a 68 Ps WagonR 1.0 MT does 0-60 in about 5.85 seconds. The CNG variant is probably slower (with less power and more weight).

Moving on to ATs, I found that a Celerio AMT does 0-60 in about 6.7 seconds, the rest of the 1.0 AMT gang will also be in the similar ballpark.

These are not earth shattering figures but par for the course. Better than 1.0 AMT numbers.

As far as 0-100 is concerned, Tata's own Punch AMT and Altroz DCT take about a month to do it (17 seconds was it?). Even if this takes 3 months to get there, there are only a handful places in the country you can legally drive at 100+ kmph. Look up trip logs on this forum and you will find that the cruise speed on most EV road trips is about 90kmph regardless of whether it is the Nexon, ZS or Kona.

Also, does it really matter? Is the CNG gang (which looks specifically for lower running costs) going to be worried about it? If I were them, I would be elated with just the space in the boot!! Tiago EV does have more boot space than a DZire CNG! Doesn't it? And an Automatic! Does any CNG car come with an automatic? Also NCR people will be keen to know that this doesn't have the 15yr deregistration sword hanging over it.

PS: The 28 lakh BYD E6 has a 0-100 of 2 seconds slower than my current ride, an 8 lakh rupee Diesel hatchback.
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Old 1st October 2022, 09:20   #283
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Re: Tata Motors announces Tiago EV. EDIT: Launched at Rs. 8.49 lakh; offers 315 km range

Quote:
Originally Posted by antz.bin View Post
The brochure mentions power output of the base variant as 45Kw and not 45 Ps.

45Kw = 60 Ps.
Thank you. This has been pointed out multiple times, yet repeated lengthy posts have been made with wrong assumptions.

Makes you wonder if this "straw man" style argument is being made intentionally. There are a lot of things you can complain about Tiago EV, but saying its grossly under powered is plain wrong.

It may not be for everyone, but Tiago EV is a well designed, well priced EV for city commutes. It's all up to execution now, if they can deliver to meet demand and maintain decent ASS, then this will be a game changer.
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Old 1st October 2022, 10:48   #284
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Re: Tata Motors announces Tiago EV. EDIT: Launched at Rs. 8.49 lakh; offers 315 km range

Has anyone informally booked the car yet? I am really tempted to get this as a second car but the first batch of 10k cars will probably be sold out on Day 1 on Oct 10. Quite like buying iPhones on Big billion Day Flipkart sale.

Last edited by Pancham : 1st October 2022 at 10:49.
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Old 1st October 2022, 10:59   #285
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Re: Tata Motors announces Tiago EV. EDIT: Launched at Rs. 8.49 lakh; offers 315 km range

I have paid the booking amount for Tiago ev XZ+ LR version. I feel at around 11.75 L on road, it is terrific value for money. I had earlier booked a Nexon EV and cancelled as I felt I am spending too much above my comfort zone.

Few points in the thought process:
1. I have a daily drive of about 40+ Kms. So this should translate into a considerable savings of around 6 -7k Kms per month. Anticipates low maintenance costs as well.

2. If running costs are low (I am planning to install solar power at home so should be almost 0), I feel it might lead to us go out for a drive more often (Like a drive to the beach 30 Km away). The more you drive, the savings in running costs should be more than the cost of the car itself. Since the battery and motor is covered for 8 year/ 1,60,000 Kms. I am good till then. Even if the state of resale value at that point is uncertain, we would have recovered the cost of the car by then. I am hoping this would result in us going out for a drive more often.

3. The IT benefits for EV car loan is applicable only for loans granted until 31 March. The deliveries for Tiago EV will begin only by Jan, so I am not sure if Altroz/Punch EV would arrive by then. Might shift the booking if the deliveries are in sight and the increase in cost is manageable.

4. Not sure how long the benefits (low road tax) lasts. With increasing adoption this might be reduced or completely taken off. This could increase the cost later. The IT benefits on car loand for example is not applicable post March 2023.

Mod Note: Our Tata Tiago Preview has been taken live at this link. Please continue the discussion over on the new thread. Thanks!

Last edited by Aditya : 1st October 2022 at 11:06. Reason: Link to preview added
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