Ask any installer in the Mumbai belt when they are busiest with faults and the answer is the same: the fortnight after the rain sets in. Systems that ran without complaint through the dry months fail in clusters, and the causes repeat year after year.
Almost all of it is preventable in May for a fraction of what it costs to fix in July.
Why the monsoon is the real stress test
Three conditions arrive together and compound each other: sustained water, sustained humidity, and voltage instability from a grid under strain. A weakness that a dry month tolerates — a slightly loose gland, a marginal power supply, a hairline crack in a junction box — becomes a failure when all three apply at once.
This is also why monsoon faults cluster. It is rarely one unlucky camera; it is several marginal installations reaching their limit in the same week.
The five monsoon failures we see every year
- Water ingress at the cable joint. By far the most common. The camera housing is usually rated for rain; the connector behind it frequently is not.
- Condensation inside the dome. Warm humid air enters, cools against the glass, and fogs it. The camera works perfectly and sees nothing. Worst at night, because infrared reflects off the fog.
- Corroded connectors and terminals, producing intermittent faults — a camera that drops out in the rain and returns when it dries, which is maddening to diagnose and easy to misattribute to the camera.
- Power supply failure from voltage swings. Supplies are usually the first casualty of an unstable grid, and a failing supply often takes several cameras with it, which looks like a recorder problem.
- Rodents and insects seeking shelter. Cable damage inside conduit and trunking spikes in the rains, and nests in a junction box hold moisture against the terminals long after the rain stops.
Water gets in at the joint, not the camera
This is the single most useful thing to understand. Camera housings carry an ingress rating — typically IP66 or IP67 — and generally live up to it. The failure point is almost always the junction: the cable gland, the connector behind the camera, or the box the joint sits in.
Three details separate an installation that survives from one that does not:
- The joint is inside a properly sealed box, not wrapped in tape and left under an eave.
- The cable enters from below or forms a drip loop, so water running down the cable falls away instead of tracking into the connector.
- The gland is the right size for the cable. An oversized gland is an open hole with a rubber ring in it.
None of these cost anything meaningful at installation. All of them are expensive to retrofit on a wall at height in the rain.
What to check in May, before it starts
A pre-monsoon visit is the highest-value service call of the year. What it should cover:
- Every junction box opened, inspected for moisture and corrosion, and resealed
- Cable entries checked for drip loops and correctly sized glands
- Camera housings and domes cleaned, and dome seals checked for perishing
- Mounting brackets checked for rust and secure fixing, before wind loads arrive
- Power supply output measured under load, not just confirmed as present
- Conduit and trunking checked for rodent damage and open ends
- Earthing checked — the one item most often skipped and the one that matters most in a lightning-prone season
If you hold a maintenance contract, ask that one of the year’s scheduled visits be timed for May rather than falling wherever the calendar puts it. A visit in April or May prevents faults; the same visit in August documents them.
What to do when a camera fails mid-monsoon
Resist the instinct to replace the camera immediately. An intermittent fault that appears in rain and clears in dry weather is almost never a failed camera — it is water at a joint or a failing supply, and a new camera on the same joint fails the same way within weeks.
Ask the engineer to test the supply voltage under load and open the nearest junction before any hardware is swapped. If a camera is genuinely replaced, ask what was found at the joint. “Nothing” is a sign the diagnosis has not happened yet.
Common questions
What does the IP rating on a camera actually mean?
Two digits: the first is protection against solids, the second against water. IP66 means dust-tight and able to withstand powerful water jets; IP67 adds temporary immersion. For outdoor use in this climate, IP66 is a sensible floor - but the rating applies to the camera housing only, not to the cable joint behind it, which is where most water actually enters.
Can a fogged dome be fixed, or does the camera need replacing?
Usually fixed. Cleaning the dome, replacing a perished seal and in some cases adding a desiccant pack resolves most condensation. Replacement is only warranted if moisture has been inside long enough to affect the lens assembly or the sensor, which the engineer can tell by inspection.
Should cameras be switched off during heavy rain or a storm?
No - that is when you most need them, and switching off does not protect the hardware from water. What does protect it is proper earthing and surge protection on the power supply, which is a design item rather than something to manage day to day.