AWS

Not sure if it’s true, I have heard from my builder that soil test results are now lodged with BCA/SLA (I am not sure specifically which agency) and if your immediate neighbour has just done rebuild recently, you can use his soil test result on request from that specific agency. Maybe the result can be used as long as it’s not too far away. I may be wrong but there will be cost savings if it’s true.

The other 10A breaker is for the pool pump? I suspect there’s water that got into your buried cable that cause the circuit issue. Or there’s water that got into the light causing the issue.

To add to what snoozee said, also do a push to test the RCCB (CD240B) module. If it trips, leave it at the tripped position and then work on swapping the timer and feed back further.

You can engage painting contractors that have extension cranes with cage for a single worker that can extend to the backyard from the front gate. The position of the crane may or may not block your neighbor’s gate access. If your land’s depth is very deep, then there is another method which contractors can use is to go to your roof and install support on the roof edge so that the worker can carabiner down the side wall to do the painting. These 2 methods will have least risk of damaging your neighbor’s roof and most times they won’t object.

I am not sure about other brands but my UniFi system is able to allow me to create different WiFi networks with controllable excess. I think other brands should be able to do that too. Managed switch has more functionality compared to unmanaged ones. And the price differences is worth it in the long term due to your required functionality. If the NVR is quite, it means there is less air flow and good chance the hard disk won’t last long. Unless you are willing to pay much more for SSD.

Red outline is the box. Green outline is the SPD. To remove the SPD, unscrew the 4 visible screws at the perimeter of box and out pops the box cover. Then use a Philips P2 to loosen all the cable connections. To remove the SPD: The will be a spring loaded metallic clamp. Use a flat head screw drive to push down the clamp’s recessed hole to loosen the clamp as show in red circle outline The blue rectangle outline is the DIN Rail where the SPD’s clamp latches on to give support. For a Type1+Type2 combi SPD, I will recommend Hager SPA401or DEHN 941310. For around SG$500-$700, is only a fraction of your hi fi setup, not even 3% of an amp. KAM is made in China, too cheap to trust. Do note the KAM is Type3 and you will need a Type3 to protect your setup and needed to be as close as possible to your setup. You can consider DEHN 953205. This is a single phase Type3 SPD. It is about SG$100+ from Amazon. DEHN & Hager mostly made in Germany.

For the replacement unit, you can source for a Type1+Type2 from e-commerce platform. Almost all foot print for 3P+N is same. You can use back the same housing. If you are hands on, off the breaker before the meter before disconnecting. Your meter display will be off too but it’s alright as there isn’t any alarm to be triggered. Once the meter display is gone, it further confirm that there is no live current downstream. Just don’t contact the neutral and earth wires.

It’s easy to swap out and if you switch off the main breakers before the PUB’s meter at the meter compartment, not the DB ones, it’s 100% safe. The life span of a SPD is not dependent on the number of strikes but on the total amount of energy being diverted to earth since installation. Once the varistor or gas discharge tube life span is used up, the indicator will turn red and it’s time to replace. Some SPD comes with a FM function and able to warn owner through a LED display or an audio alarm that the SPD is no longer functioning and need replacement.

I asked around previously from electrical supply shops locally and was shown this particular brand ‘kam’ for sale. It’s made in China. Price around $13 each and only single phase available, not 3P+N.

Pete, the SPM440E is a Type2. Did you managed to install any Type1? Further, the 3 LIVE & 1 Blue NEUTRAL cables tapped from the MCCB inlet connection looks very long. Any one phase cable length + PE cable looks like more than 50cm. There will be a certain percentage of pass through for Type2 surge and if you don’t have Type1 installed, there will be 100% pass through of Type1 surge.

Our 3 phase system is using TT connection and usually referenced as 3P+N. So you will need a 4 pole device for all connections. In layman term, you need 4 inlet connections and 4 outlet connections for any single device. Unless you split each phase with 1 device. Example will be the incoming circuit breaker as shown in your earlier post. In that picture, you can see 3 small white boxes and a smaller black box. The 3 white boxes each house a single phase breaker (63A or 100A depends) to connect one of the 3 LIVE phases. The black box is a direct connection of the Neutral phase which don’t need a breaker. So, if you can find a 20kA times four SPD, it can be used too. Make sure the SPD has 3P+N=4 connections. For the SPD installation inside you house’s DB, you can use 10kAx4=40kA. Do note: Class 1 also known now as Type 1, Class 2 also known as Type 2 and Class 3 known as Type 3. They are basically the same classification for the SPD. Type 1 will be expensive and not easy to find as most house owners don’t know it is highly recommended. It is not mandated by PUB when they sign off the main incoming electrical panel after installation by electrical sub-con. Personally, I don’t think PUB care if the house gets a lightning strike(taken care by the lightning protection system signed off by BCA)and in turn causes a surge current in the house’s electrical circuit and killing/shortening life span of your expensive equipments/household items. As long as the basic requirement(63A breaker and/or 300 mA RCCB) is there, and most important of all, the meter is running to bill owner at the end of the billing cycle, PUB won’t care. Anything damaged inside the house is under owner’s charge. The 63A breaker is to prevent overload/surge current at the sub-station from entering your house or cause fire at the incoming electrical panel cluster which you can legally take action. A Hager brand Type 2, 40kA total, 3P+N will cost around $250-$270 each, available at some local electrical supply shop. I am using one each for my 2 in-house DBs. Type 3 sold at electrical supply shops were China made and I don’t trust. You can go online e-commerce to search for DEHN or Phoenix Contact, both brand made in Germany. Typical e-commerce price of Type 3 in the region of $150-$200 each. For Type 1 you can look at DEHN. But DEHN mostly comes with Type 1 combined with Type 2. In theory, if this device is installed in your incoming electrical panel, it will arrest the Type 1 and Type 2 classified surge but because of the long cable length that run from your incoming panel to inside your house’s DB, some Type 2 surge (caused by lightning) will be picked up by this long length of cable and cause some surge at your in house DBs. One solution is to install another Type 2 only SPD at the in house DBs. They are relatively cheap at $270 max to protect your motor driven devices like water pumps, air con compressors, fridge compressors, fans motor etc. And because they are in the secondary level Type 2, they will last a long time. DEHN Type1+Type2 will cost around $600 from e-commerce but local distributor selling at $1000+ with installation another $500+. Note: Type 3 SPD is for protection of electronic devices and need to be as close as possible to device to be protected. Am analogy is those extension sockets with surge protection integrated. Example brand like Belkin. Because it’s a all in one commerce product, the small SPD integrated into the extension bar will not be able to neutralize the Type 3 surge effectively. From my own experience, I have noticed a marked reduction in motor driven noise (fan motor, fridge compressor) in my air con fan coils, fridges, and my network cluster. But it could be just me.

The first picture should be your main gate incoming DB (or referred as incoming electrical panel) because it has your incoming mains and your meter. It will be difficult to fit the SPD outside the incoming main gate electrical panel due water ingress issue causing trips or safety concerns. Further, there is a requirement wire length for each phase with connection joint from the MCCB outlet joint to the SPD inlet joint PLUS the length of the earth wire to the ground bar(shown in picture with 2 blue non conducting foot mount) total not to exceed 50cm. Once this maximum length is exceeded, there will be a drop in effectiveness to divert the surge current to earth due electrical inductances. From what I can see in the first picture, there is still space available but may require re-positioning the MCCB (small white box with some red colored ON/OFF toggle lever) This looks like an old ABB brand item.

Hi Pete The first entry of surge current is at the gate post where the electrical meter is located. If you are having 3 phase 63A, you will see 4 cables (L1+L2+L3+N) L=Live and N=Neutral. The 3 Live wires are Black, Grey, Brown. The Neutral is Blue.There is also a PE (Protective Earth)!which is green/yellow and this PE will be connected to your earth rod/electrode. At the incoming (gate post), you need Class 1 SPD(Surge Protection Device)with preferred 25KA per phase. So with 3 phase + Neutral, it will be 4x25kA=100kA rating. This SPD is preferred to be installed after the MCCB but before the RCCB. If your LEW want to install after the RCCB, you may encounter sensitive tripping of the RCCB unless your LEW can find a ‘S’ type RCCB which has a time delayed tripping function. This SPD can be connected in either parallel or kelvin connection. Do discuss with your LEW. At the DB, only Class 2 SPD is required. You will need minimum 10kA per phase protection which means 40kA total. This SPD needs to be install upstream of your DB’s MCCB & RCCB. Connection is either parallel or kelvin connection. To enhance protection to your Hi Fi equipments, you will further need a Class 3 SPD. This SPD should be installed as near to your equipment as possible. This is preferred to be just before your Hi Fi’s voltage regulator/stabilizer if you have one. Based on your description of using one phase dedicated to your Hi Fi system, install this Class 3 SPD after your wall power outlet and before the voltage regulator. You can install as many Class 3 SPD as required depending what equipments you need to protect. One power outlet=1 SPD. Connection in parallel or series. If series, there is a limit current of 25A. If connect in parallel, will be much higher. In summary, you will need: 1x Class 1 SPD, 1x Class 2 SPD per DB, multiple Class 3 SPD. Cost of SPD in descending order: Class 1>Class 2>Class 3. Hope these helps.

Some owners put in a LD(day or month)in the contract. Most builders if see a LD in a contract, will load in a sum to the final cost. Frankly speaking, they are not stupid that the owner insist on a LD in the contract and builder just accept the job without loading. Nowadays, jobs are plenty and they can choose. Whatever the final contract sum, the builder’s QS will definitely know the full cost to the builder before loading a 20-30% profit before accepting the contract or taking part in the tender.

Just for matter of interest for all, in China, the sellers of tiles are referenced to square meter. In Singapore, we use square feet. The factor differences is 10.7. A common mill MIC tile starts at SG$2/sf in Singapore. In China, this same tile is selling at SG$2/sm. The profit margin is 10 times excluding freight charge for the Singapore sellers. Factor in the freight cost of around $1800 average pre covid, excluding GST, the profit margin is still a good 7-8 times. A 20T container can fit in easily 800 square meter for tiles at 10mm thickness or 400 square meter for granite/marble of 20mm.